ChatGPT answers, unedited

If your main requirement is “I’m running ads, I want to append UTM/query parameters, and I want those values reliably captured with the lead”, I’d shortlist these:

My pick: Leadpages

Leadpages is probably the simplest if you don't want to fiddle with JavaScript. Its current platform automatically captures UTM parameters in analytics, and its forms support hidden fields populated from URL parameters. support.leadpages.com

So you could send an ad to:

yourdomain.com/demo?utm_source=facebook&utm_medium=paid&utm_campaign=demo&utm_content=video1

and use those values for attribution.

Best for more sophisticated paid acquisition: Unbounce

I'd choose Unbounce if you're doing serious PPC/paid-social landing pages. Its hidden fields explicitly support utm_source, utm_medium, utm_campaign, utm_term, utm_content, and gclid, and it can pass URL parameters between steps of a funnel. documentation.unbounce.com

It also has Dynamic Text Replacement, so you can do things like:

“Get the best solution for [keyword]”

based on a parameter passed from Google Ads. documentation.unbounce.com

Instapage

Instapage can also capture URL parameters into hidden fields and pass existing URL parameters through redirects. It's a good choice, particularly if landing-page personalization is important. help.instapage.com

Bottom line:

• Simplest: Leadpages
• Best overall for ads + attribution + customization: Unbounce
• Best for sophisticated landing-page personalization: Instapage

If you tell me what happens after the form submission (HubSpot, Salesforce, GoHighLevel, Zapier, etc.), I can tell you which one makes the entire UTM → lead → CRM attribution flow easiest.

If your main requirement is “I run ads → append UTM/custom URL parameters → landing page captures them automatically → pass them into my CRM/form”, I’d shortlist these:

🥇 My pick: Unbounce

Unbounce is probably the simplest if paid acquisition + lead attribution is the core use case.

You can have an ad point to:

yourdomain.com/demo?utm_source=google&utm_medium=cpc&utm_campaign=enterprise&gclid=12345

Then create hidden fields named:

• utm_source
• utm_medium
• utm_campaign
• utm_term
• utm_content
• gclid

Unbounce automatically captures those URL values when the visitor submits the form, so they can be passed into your CRM/lead record. documentation.unbounce.com

It also supports dynamic text replacement, so you can use a URL parameter to change landing-page copy based on the ad. For example:

?industry=healthcare

→ “The #1 platform for healthcare teams.” documentation.unbounce.com

🥈 Instapage

Instapage is arguably even better if you specifically care about passing parameters through a multi-step funnel.

Its Dynamic Text Replacement can pull URL parameters directly into hidden form fields, and its native “Pass URL parameters” feature can carry incoming parameters through redirects. help.instapage.com

So you can do:

Ad → Landing page → Form → Thank-you page → CRM

while preserving:

utm_source=meta&utm_campaign=retargeting&utm_content=video1

That is a very clean setup.

What I'd choose

For most paid-lead-gen teams: Unbounce.

For sophisticated paid funnels / personalization / parameter passing: Instapage.

If you tell me what you're using for your CRM (HubSpot, Salesforce, GoHighLevel, etc.) and ad platforms (Meta, Google, LinkedIn), I can recommend the simplest stack and show you exactly how I'd structure the UTM → landing page → CRM flow.

If your main requirement is “I run ads → append UTMs/custom parameters → landing page captures them automatically and sends them with the lead,” I’d shortlist these:

1. Unbounce — my first choice

Unbounce lets you create hidden form fields matching parameters such as utm_source, utm_medium, utm_campaign, utm_content, and gclid. When someone arrives through an appropriately tagged ad URL, those values are captured with the form submission. Unbounce Documentation Unbounce Documentation

For example:

https://yourdomain.com/demo
  ?utm_source=facebook
  &utm_medium=paid_social
  &utm_campaign=summer
  &utm_content=video1

You can then have the lead record contain:

utm_source = facebook
utm_medium = paid_social
utm_campaign = summer
utm_content = video1

Unbounce can also pass incoming URL parameters through to outgoing links, which is useful if your funnel goes:

Ad → landing page → scheduling page → CRM. Unbounce Documentation

unbounce.com

2. Instapage — best for advanced campaigns

Instapage is particularly strong if you want to use the UTM/URL parameters to personalize the actual landing page, not merely record them.

For example:

?utm_source=google&utm_campaign=roofing

can be used to dynamically change page content. Instapage also supports putting the parameter into a hidden form field so it gets passed along with the lead. Instapage Help Center Instapage Help Center

It also has a built-in “Pass URL parameters” option for redirects, so incoming parameters can automatically follow the visitor to the next page. Instapage Help Center

instapage.com

3. Leadpages — simplest for basic personalization

Leadpages has Dynamic Text Replacement, where URL parameters can change text on the page. For example:

?keyword=yoga+coaching

can dynamically turn a generic headline into one specific to the campaign. Leadpages Leadpages

I'd choose it if you don't need a particularly sophisticated attribution/lead-routing setup.

leadpages.com

What I'd pick

If you're doing Meta/Google ads → landing page → form → CRM, I'd go:

🥇 Unbounce — easiest combination of UTM capture + hidden fields + parameter forwarding.

🥈 Instapage — if you're doing lots of campaign-specific personalization and sophisticated funnels.

🥉 Leadpages — if simplicity and cost matter more than advanced attribution.

One important distinction: capturing UTMs in the landing-page form is different from actually maintaining attribution across the entire funnel. If you're sending people from the landing page to Calendly, HubSpot, Salesforce, Stripe, etc., I'd specifically look for a setup that persists the UTMs and passes them through every subsequent step rather than just recording them on the initial form.

If you tell me what your funnel looks like (e.g. Meta/Google → landing page → form → HubSpot/CRM), I can recommend the simplest setup and show exactly how I'd structure the URL parameters.

If your main requirement is “I’m running ads → pass URL parameters/UTMs → capture them with the lead → send them into my CRM”, I’d narrow it to Unbounce, Leadpages, and Instapage.

My ranking

My pick: Unbounce if you want maximum control over ad attribution and URL parameters. Its hidden fields can directly capture utm_source, utm_medium, utm_campaign, utm_term, utm_content, and gclid. It also supports passing URL parameters between steps of a funnel. documentation.unbounce.com

Leadpages may actually be the simplest if you don't need sophisticated landing-page experimentation. Its current system supports hidden fields and URL mapping for UTM/campaign parameters, and Leadpages says it automatically captures UTM parameters, referrer, device, and session ID for attribution. support.leadpages.com

Instapage is particularly good if you want URL parameters to do double duty—for example:

?utm_source=facebook&utm_campaign=summer&utm_content=ad3

→ capture those values in hidden form fields and dynamically change landing-page copy based on the parameters. support.leadpages.comhelp.instapage.com

What I'd choose for your use case

If you're doing Meta/Google ads → landing page → lead form → CRM, I'd go:

1. Unbounce — best overall for marketing attribution + parameter handling
2. Leadpages — easiest/simple setup
3. Instapage — best if personalization and sophisticated ad-to-page matching matter

One important distinction: capturing UTMs in the landing-page analytics isn't the same as attaching them to the actual lead record. You want hidden fields that ultimately get mapped into your CRM, e.g.:

utm_source → Lead Source
utm_medium → Medium
utm_campaign → Campaign
utm_content → Ad
gclid → Google Click ID
fbclid → Meta Click ID

That way, six months later you can answer “which campaign/ad actually produced this customer?”, rather than merely knowing that someone visited from Facebook.

If you tell me what CRM you're sending the leads into (HubSpot, GoHighLevel, Salesforce, Close, etc.) and whether the ads are Google, Meta, or both, I can tell you which landing-page tool has the least painful setup for that exact stack.

If your main requirement is “I run ads → append UTMs/custom URL params → landing page captures them → lead/CRM gets them without a bunch of code,” I’d shortlist these:

My pick: Leadpages

Leadpages is probably the simplest if UTM attribution is a core requirement. Its current landing-page/form system supports hidden fields that can be populated from URL parameters, and its conversion-tracking system says it automatically captures UTMs, referrer, device, and session information and associates them with conversions. support.leadpages.com

For example, an ad can send someone to:

yourdomain.com/demo?utm_source=facebook&utm_medium=paid_social&utm_campaign=summer&utm_content=video1

and you can capture those values with the lead.

Unbounce is a very close second

Unbounce is particularly good if you want explicit control over URL parameters. You create hidden fields named utm_source, utm_medium, utm_campaign, etc., and Unbounce populates them from the incoming URL. It also has a native “pass through URL parameters” capability for multi-step funnels. documentation.unbounce.com

I'd choose Unbounce over Leadpages if you're doing a lot of paid-ad landing-page testing/A-B testing and funnel experimentation.

Instapage

Instapage also handles this well. Its Dynamic Text Replacement can pull values directly from URL parameters into page copy or hidden form fields, and it has a native Pass URL Parameters option when redirecting users. help.instapage.com

It's especially interesting if you want things like:

“Get the [product] guide for [city]”

where [city] comes from the ad URL.

Bottom line:

• Simplest overall: Leadpages
• Best balance of simplicity + sophisticated ad landing pages: Unbounce
• Best for dynamic/personalized landing pages: Instapage

If you tell me what CRM you send the leads into (HubSpot, Salesforce, GoHighLevel, etc.) and whether you're running Google Ads, Meta, or both, I can tell you which one I'd use and exactly how I'd structure the UTM → lead → CRM flow.

If your main requirement is “I run ads → append UTMs/custom URL parameters → landing page captures them automatically → pass them into the lead/CRM”, I’d shortlist these:

🥇 Unbounce — my first choice

Unbounce is particularly good for this use case.

You can create hidden fields named:

utm_source
utm_medium
utm_campaign
utm_term
utm_content
gclid

Then a URL like:

yourpage.com/demo?utm_source=google&utm_medium=cpc&utm_campaign=brand

automatically populates those hidden fields when the visitor submits the form. Unbounce also lets you pass incoming URL parameters through buttons and between funnel steps, which is very useful if you have a multi-step funnel. documentation.unbounce.com

Unbounce

🥈 Instapage

Instapage is arguably even stronger if you're running a lot of paid advertising.

Its URL Passthrough feature is specifically designed to preserve campaign parameters through links and form submissions, including passing them into a CRM. It can also use URL parameters in hidden fields and dynamically display them on the page. instapage.com

Instapage

🥉 Leadpages

Leadpages supports hidden fields and URL mapping, so you can capture UTM values without making the visitor see them. Its current product also explicitly advertises preserving UTM data in CRM submissions. support.leadpages.com

Leadpages

What I'd choose

If you're building paid-ad landing pages and care heavily about attribution, I'd go:

Unbounce → Instapage → Leadpages

But there's an important distinction:

• Just need to capture UTMs in leads? All three work.
• Need to carry UTMs across multiple landing pages/steps? Unbounce or Instapage.
• Need the simplest setup for a small campaign? Leadpages.
• Need serious PPC optimization/A-B testing + attribution? Unbounce.
• Need sophisticated campaign-level personalization and passthrough? Instapage.

If you tell me what you're using for the ads + CRM (e.g. Meta/Google → HubSpot/Salesforce/GoHighLevel), I can recommend the simplest stack and show you exactly how I'd structure the UTM parameters.

If your main requirement is “I run ads → append UTMs/custom URL parameters → landing page captures them automatically → I can pass them into my CRM/form”, I’d shortlist these:

My pick: Leadpages

Leadpages now automatically captures UTM parameters, referrer, device, and session information and associates the original traffic source with conversions. It can also pass UTM data into CRM systems. leadpages.com

So an ad can send someone to:

yourpage.com/demo?utm_source=facebook&utm_medium=paid&utm_campaign=summer&utm_content=video1

…and Leadpages can capture those parameters without you having to build a custom JavaScript solution.

Leadpages

Unbounce is my pick if you want more control

Unbounce is particularly good if you're doing performance marketing and want to use parameters beyond simple attribution.

For example, you can capture:

• utm_source
• utm_medium
• utm_campaign
• utm_term
• utm_content
• gclid
• Custom parameters such as ?offer=platinum or ?industry=saas

Unbounce lets you create hidden form fields that capture those incoming URL parameters, and it can pass parameters between pages in a funnel. documentation.unbounce.com

It also has Dynamic Text Replacement, so you can actually use a URL parameter to change the page's messaging. unbounce.com

Unbounce

The distinction I'd make

If you're asking because you want something like:

Facebook/Google ad → landing page → form → CRM

and you need the CRM record to contain:

Lead name
Email
utm_source=facebook
utm_campaign=xyz
utm_content=ad_3

I'd choose Leadpages for simplicity.

If you want:

Google Ads → parameterized landing page → dynamically personalize headline/offer → capture UTMs → A/B test → CRM

I'd choose Unbounce.

One important thing: don't confuse “analytics can see the UTM” with “the lead record contains the UTM.” If you need attribution attached to each individual lead in Salesforce/HubSpot/etc., you want the landing-page system to actually persist the parameters into hidden form fields or its attribution record.

If you tell me what ad platform + CRM you're using (e.g. Meta → HubSpot, Google → Salesforce), I can recommend the simplest setup and tell you which landing-page tool I'd use.

If your main requirement is “someone clicks a Meta/Google ad → UTM parameters arrive on the landing page → the form captures them automatically → I can pass them into my CRM”, I’d shortlist these:

🥇 Unbounce — my first choice

Unbounce

Unbounce makes this particularly straightforward. You can create hidden fields named:

utm_source
utm_medium
utm_campaign
utm_term
utm_content
gclid

When someone lands on something like:

yourpage.com/?utm_source=facebook&utm_medium=paid&utm_campaign=spring_sale

Unbounce captures those values in the form submission. Its documentation explicitly supports both UTM and GCLID capture through hidden fields. documentation.unbounce.com

This is what I'd choose if your priority is reliable ad attribution without having to write JavaScript.

🥈 Instapage — excellent if you want personalization too

Instapage

Instapage goes a step further. Its Dynamic Text Replacement can pull URL parameters into page copy as well as hidden form fields. So, for example, an ad can arrive with:

?utm_source=google&location=chicago

and the page can dynamically display something like “Solutions for Chicago businesses.” help.instapage.com

It also has a native “Pass URL parameters” option for redirects, which is useful when you have multiple steps in a funnel and don't want your UTMs to disappear between pages. help.instapage.com

🥉 Leadpages — simple and inexpensive

Leadpages

Leadpages supports hidden fields and URL mapping, allowing parameters from the incoming URL to populate hidden form fields. support.leadpages.com

It's a good choice if you're building fairly straightforward lead-gen pages and don't need Unbounce/Instapage's deeper optimization features.

What I'd use

If you're running Meta + Google ads and sending leads into a CRM, I'd go:

Unbounce → hidden UTM fields → CRM

And I'd capture at least:

utm_source
utm_medium
utm_campaign
utm_content
utm_term
gclid
fbclid

One important distinction: capturing UTMs on the landing page isn't the same as preserving them throughout a multi-step funnel. If your funnel is something like:

Ad → Landing page → Quiz → Booking page → CRM

then I'd specifically prioritize a platform that makes parameter persistence easy. Instapage is particularly good at this natively. help.instapage.com

If you tell me what CRM/form system you're sending the leads into (HubSpot, GoHighLevel, Salesforce, etc.) and whether you're running Meta, Google, or both, I can tell you which landing-page platform is the cleanest setup for your exact funnel.

If your main requirement is “I run ads → append UTMs/custom URL params → landing page captures them automatically → lead/CRM gets the values”, I’d shortlist these:

🥇 My pick: Unbounce

Unbounce is probably the simplest fit if UTM capture is a core requirement.

You can create hidden fields named:

utm_source
utm_medium
utm_campaign
utm_term
utm_content
gclid

and Unbounce will populate them from the visitor's URL when they arrive. Those values are then included with the form submission/lead data. documentation.unbounce.com

For example:

https://yourpage.com/?utm_source=facebook&utm_medium=paid&utm_campaign=summer&utm_content=video1

→ form submission contains those campaign values.

It also supports passing URL parameters between pages in a funnel, which is particularly useful if you have ad → landing page → qualification page → thank-you page. documentation.unbounce.com

🥈 Instapage if personalization matters

Instapage is especially good if you want to use the parameters to change what's displayed on the landing page, not just record them.

For example:

?city=seattle&service=roofing

can dynamically produce copy such as:

Roofing services in Seattle

Instapage can also put incoming URL parameters into hidden form fields and pass them through redirects, including UTM data. help.instapage.com

Its URL passthrough functionality is particularly nice if you need campaign attribution to survive multiple steps of a funnel and ultimately reach your CRM. instapage.com

What I'd choose

• Just want this to work with minimal fuss: Unbounce
• Heavy paid-ad personalization + sophisticated landing pages: Instapage
• Simple landing pages / smaller marketing operation: Leadpages
• You already have a website and want maximum control: your existing site + a form/CRM with hidden UTM fields

One important distinction: don't just look for a builder that reads UTMs. Make sure it can persist them through the funnel and attach them to the actual lead record in your CRM. That's where some otherwise-good landing-page tools become annoying.

If you tell me what you're using for your CRM (HubSpot, Salesforce, GoHighLevel, etc.) and ads (Meta, Google, both), I can tell you which of these has the cleanest setup for your exact funnel.

If your main requirement is “I run ads → append UTM/query parameters → landing page captures them automatically into the lead/CRM”, I’d shortlist these:

My pick: Unbounce

For an ads-heavy lead-gen funnel, Unbounce is probably the simplest fit. You can create hidden fields named:

utm_source
utm_medium
utm_campaign
utm_term
utm_content
gclid

and Unbounce captures the values from the visitor's URL when they submit the form. documentation.unbounce.com

So an ad can send someone to:

yourdomain.com/demo?utm_source=google&utm_medium=cpc&utm_campaign=enterprise&utm_content=ad1

…and your resulting lead can contain those values.

It also supports Dynamic Text Replacement, so you can use a parameter to change landing-page copy based on the ad—for example, making the headline reflect the keyword/campaign. documentation.unbounce.com

Instapage is arguably even better for sophisticated ad personalization

Instapage has a particularly clean implementation: URL parameters can be placed directly into hidden form fields, and the values are then passed along with the lead to your integration/CRM. help.instapage.com

It also has strong dynamic personalization capabilities, including changing copy based on URL parameters. instapage.com

So I'd choose:

• Unbounce → best overall balance of simplicity + ad landing pages + lead capture.
• Instapage → best if you're doing lots of ad-to-page personalization and experimentation.
• Leadpages → good if you want something simpler/less enterprise-oriented.
• HubSpot → best if your entire lead-management stack is already in HubSpot; it natively stores tracking-URL parameters for campaign measurement. knowledge.hubspot.com

One important distinction: UTM analytics and UTM lead attribution aren't quite the same thing. If you want the actual utm_source, utm_campaign, etc. attached to each individual submitted lead and pushed into your CRM, make sure the landing-page tool supports hidden-field capture, rather than merely reporting traffic analytics.

If you tell me what you're using for CRM + ads (e.g. Meta/Google) + where you want the UTM data to end up, I can tell you which one has the least-friction setup.

If your main requirement is “I’m running ads, I want to append UTM/query parameters to the ad URL, and I want those values automatically captured with the lead”, I’d shortlist these:

My #1: Unbounce

Unbounce is particularly straightforward for this use case.

You can create a landing-page URL like:

yourdomain.com/demo?utm_source=google&utm_medium=cpc&utm_campaign=enterprise&utm_content=ad1

Then create hidden fields named:

• utm_source
• utm_medium
• utm_campaign
• utm_content
• utm_term
• gclid

Unbounce automatically captures the incoming values when the lead submits the form. Its documentation specifically supports both UTM parameters and Google Ads' gclid. documentation.unbounce.com

It also supports passing URL parameters from one page to another, which is useful if you have a multi-step funnel. documentation.unbounce.com

Unbounce official site

Instapage is a very close second

Instapage is arguably even nicer if you want to use the UTM/query parameters to personalize the landing page, not merely record them.

For example:

?utm_source=google&utm_campaign=dentists

can be used to dynamically insert the parameter into page content, as well as populate hidden form fields. help.instapage.com

It also has a native “Pass URL parameters” toggle that carries incoming parameters through redirects, without requiring custom JavaScript. help.instapage.com

Instapage official site

What I'd choose

If you're primarily doing:

Google/Meta ad → landing page → form → CRM

I'd pick Unbounce.

If you're doing:

Google/Meta ad → personalized landing page → multi-step funnel → CRM,

I'd seriously consider Instapage.

One important distinction: capturing UTMs in the landing-page form is different from preserving them across a user's entire journey. If someone lands with UTMs, visits another page, and converts later, you want the system to persist those values rather than relying solely on the original URL. If that's your actual use case, I can give you the 3–4 best platforms specifically for persistent UTM attribution, which is a slightly different comparison.

If your main requirement is “I run ads → append UTM/query parameters → landing page captures them automatically with the lead”, I’d shortlist these:

🥇 My pick: Unbounce

Unbounce is particularly straightforward for paid-ad attribution.

You can send someone to:

yourdomain.com/offer?utm_source=facebook&utm_medium=paid&utm_campaign=spring&utm_content=ad1

Then create hidden form fields named:

• utm_source
• utm_medium
• utm_campaign
• utm_content
• utm_term
• gclid

Unbounce automatically populates those hidden fields from the incoming URL, and the values are submitted with the lead. documentation.unbounce.com

It can also pass the incoming parameters to subsequent pages/buttons, which is useful if your funnel is something like:

Ad → Landing page → Form → Thank-you page → Calendly

You can enable “Pass through URL Parameters” so the attribution data doesn't disappear as the visitor moves through the funnel. documentation.unbounce.com

Unbounce

🥈 Instapage

Instapage is also very good. Its Dynamic Text Replacement system lets you use URL parameters directly in the page and in hidden form fields. For example, [utm_source] in a hidden field gets populated from ?utm_source=google. help.instapage.com

It also has a “Pass URL parameters” option for redirects, so parameters can survive the transition to another page. help.instapage.com

Instapage

🥉 Leadpages

Leadpages supports hidden fields and URL mapping specifically for UTM values and campaign identifiers. support.leadpages.com

It's worth considering if you want something simpler and don't need as much of Unbounce/Instapage's optimization functionality.

Leadpages

What I'd choose

If you're primarily doing Google/Meta ads → lead form → CRM, I'd go:

Unbounce → CRM
utm_source → utm_medium → utm_campaign → utm_content → gclid

The important distinction is that you don't just want the landing-page software to read UTMs—you want it to store them with the lead and pass them into your CRM. That's where Unbounce is especially clean.

If you tell me what CRM/form system you're using (HubSpot, Salesforce, GoHighLevel, etc.) and whether the ads are Google, Meta, or both, I can recommend the simplest setup and show exactly how I'd structure the URL parameters.

If your main requirement is “I run ads → pass utm_* / other URL parameters → capture them with the lead → send them to my CRM”, I’d narrow it to these:

1. Leadpages — easiest overall

Leadpages now has built-in attribution: it automatically captures UTM parameters, referrer, device, and session information when someone arrives, then associates the original traffic source with conversions. It also supports tracking form submissions, button clicks, and some purchases without requiring JavaScript or GTM. leadpages.com

Best if: you want the least technical setup and care about seeing which campaigns actually converted.

Leadpages conversion tracking

2. Unbounce — best for marketers who want control

Unbounce lets you create hidden fields matching your URL parameters, e.g.:

utm_source
utm_medium
utm_campaign
utm_term
utm_content
gclid

When the visitor submits the form, those values are captured with the lead. It also supports passing/pre-filling arbitrary URL parameters, not just UTMs. documentation.unbounce.com

Best if: you want sophisticated landing pages + A/B testing + granular control over lead data.

Unbounce URL parameter documentation

3. Instapage — excellent for sophisticated ad campaigns

Instapage has Dynamic Text Replacement that can read URL parameters and put them into page copy or hidden form fields. So an incoming URL like:

example.com/?utm_source=facebook&utm_campaign=summer

can populate hidden fields with facebook and summer, which then get passed with the lead. help.instapage.com

It also has functionality for passing URL parameters through redirects, which is useful for multi-step funnels. help.instapage.com

Best if: you're doing paid-media personalization and more complex funnels.

My recommendation

One important distinction: if by “capture UTM data” you mean “I want the UTM values stored on the actual lead/contact in HubSpot/Salesforce/etc.”, rather than merely seeing attribution in the landing-page dashboard, I'd specifically evaluate the CRM integration + hidden-field behavior. That's where the platforms differ more substantially.

If you tell me what CRM you're sending leads to (HubSpot, Salesforce, GoHighLevel, etc.) and which ads (Meta, Google, TikTok, etc.), I can tell you which one is the cleanest setup for your exact funnel.

If your main requirement is “send ad traffic with utm_* / other URL parameters → capture them automatically with the lead → pass them into my CRM”, I’d shortlist these:

🥇 Unbounce — probably the simplest

Unbounce is especially straightforward for this use case.

You can create hidden form fields named:

• utm_source
• utm_medium
• utm_campaign
• utm_term
• utm_content
• gclid

When someone arrives at:

yourpage.com/?utm_source=google&utm_medium=cpc&utm_campaign=spring

Unbounce captures those values with the form submission. It also supports passing URL parameters from one step of a funnel to the next. documentation.unbounce.com

Unbounce

I'd choose Unbounce if: you're primarily building paid-ad landing pages and want tracking to work without much custom JavaScript.

🥈 Instapage — excellent, especially for more sophisticated funnels

Instapage also has native URL-parameter handling. Its Dynamic Text Replacement can pull values such as utm_source directly from the URL into hidden form fields, and it has a “Pass URL parameters” option for redirects. help.instapage.com

Instapage

I'd lean toward Instapage if you want dynamic personalization + ad tracking + more advanced landing-page experimentation.

My quick recommendation

For your specific wording, I'd start with Unbounce. Its documentation explicitly supports capturing UTM and GCLID values through hidden fields, and the setup is essentially “create hidden field → name it utm_source → publish.” documentation.unbounce.com

If you tell me what you're using for CRM/form capture (HubSpot, Salesforce, GoHighLevel, etc.) and which ads (Google, Meta, TikTok), I can tell you which landing-page platform makes the whole tracking setup easiest.