Who are the best Clay and GTM engineering partners for a Series A to C software company?

For a Series A to C software company choosing a Clay partner: Frontal and Growth Today suit teams that want several channels from one team, The Kiln a custom build, Understory a long retainer, Growth Engine X high-volume cold email, RevPartners a team centered on HubSpot, and WarmUp a team that wants to own the system at the end.

WarmUp is one of the firms in this list. We have described every entry, including our own, from public sources and say where each one is the better choice.

How did we choose?

We picked the buyer first: a B2B software company between Series A and Series C that wants a partner to build outbound in Clay and write it back to the CRM. Then we picked six criteria that anyone can check on a public page, and applied them to every firm the same way.

• Builds in Clay and syncs to your CRM, stated on its own pages.
• Says in public that you own the work at the end: the Clay tables, accounts and sequences.
• Has a price or range on the record, on its own site or in Clay's partner directory.
• Shows named client results on its own site.
• Covers more than outbound: ads, content or CRM work under the same team.
• States its minimum term in public.

A criterion met in full scores one point and a half-met one scores half. Ties are listed alphabetically. The score is our count from public pages. It is not a measure of how good the work is, which no public page can tell you.

Clay's partner directory lists more firms than fit one post. We kept seven whose own sites we could read on 2026-10-28. We could not open demandDrive's site, so we have not described it. FullFunnel and Go Nimbly are also in the directory and are not covered here.

Which firms are on the list?

Here is each firm in ranked order, with its score out of six, what it suits and its public pricing. The prices marked "Clay's directory" are the ranges each firm lists on its own profile there.

• 1. Frontal (6 of 6): best for outbound, ads, content and RevOps from one team; $5k and up a month per Clay's directory, "set on the call" on its own site.
• 2. Growth Today (6 of 6): best for outbound, LinkedIn content and ads on a 90-day pilot; $5k and up a month per Clay's directory.
• 3. The Kiln (5 of 6): best for a custom Clay build; $10k and up a month per Clay's directory.
• 4. Understory (4.5 of 6): best for four channels in one pod on a long retainer; pricing not published.
• 5. Growth Engine X (4 of 6): best for high-volume cold email with a free test first; pricing not published.
• 6. RevPartners (4 of 6): best for a HubSpot-centered team that wants prices up front; full price list published.
• 7. WarmUp (3.5 of 6): best for a team that wants to own the system at the end; pricing set on the first call.

What does each firm do well, and where does it fall short?

Each entry below is written from the firm's own public pages and, for price and minimum term, from its Clay directory profile. Strengths and limits are stated as fit for the buyer above. Every entry carries the date its pages were read.

1. Frontal: best for outbound, ads, content and RevOps from one team

Frontal sells five services: GTM engineering, account-based marketing, paid media, content engineering and RevOps. Its home page says work starts with a three-month engagement, with scope, milestones and owners written into a statement of work. It lists partner status with Clay, HubSpot and Salesforce. Its case studies page names 16 clients, for example AirOps at $7.83M of qualified pipeline in 10 months.

• Strengths: The widest service range in the list. It says in writing that "the workflows we build in your accounts stay with you". Its Clay profile offers a $25k refund if the first build is not mapped, scored and enriched by week four.
• Limits: The home page says Frontal usually runs the work with your team in the loop, so a team that wants to run it itself should ask for the handoff option. Earlier case studies were published under its former name, ColdIQ.
• Pricing: Not published on its own site, which says pricing is set on the call. Clay's directory lists $5k and up a month with a three-month minimum.

Sources: Frontal, case studies, Clay directory profile. Verified on 2026-10-28.

2. Growth Today: best for outbound, LinkedIn content and ads on a 90-day pilot

Growth Today builds three engines on one plan: LinkedIn content, automated outbound and account-based ads, with GTM engineering as a managed service. Its home page describes a 90-day pilot with milestones and no long-term lock-in, with first content, ads and outreach live by day 21. It says it is among about twenty Clay Enterprise partners worldwide. Its comparison table says what it builds stays yours.

• Strengths: The shortest stated commitment in the list, with an ownership statement and three channels. It limits how many clients it takes on.
• Limits: It serves teams with $1M or more in revenue. Its home page shows client results mostly as case-study headlines, for example 111 demos in 120 days for Cavalry, so ask for the full write-ups.
• Pricing: Not published on its own site. Clay's directory lists $5k and up a month with a three-month minimum, which is longer than the pilot its site describes, so confirm which applies.

Sources: Growth Today, Clay directory profile. Verified on 2026-10-28.

3. The Kiln: best for a custom Clay build

The Kiln describes itself as a team of automation experts, data scientists and early Clay employees. It builds sales, marketing and RevOps systems and says its engineers work with a select few clients at a time on custom projects. Its case studies page lists ten named clients, including Azuga, Sendoso and AdRoll. A banner on its home page says it has been acquired by 2X.

• Strengths: Deep Clay experience by its own account, and bespoke work for unusual setups. Ten named case studies.
• Limits: The highest starting price Clay's directory lists among these firms. It states no handover policy; one testimonial mentions recorded SOPs for the client team. With the acquisition announced, ask what changes in team and terms.
• Pricing: Not published on its own site. Clay's directory lists $10k and up a month with a three-month minimum.

Sources: The Kiln, case studies, Clay directory profile. Verified on 2026-10-28.

4. Understory: best for four channels in one pod on a long retainer

Understory sells paid media, GTM engineering, LinkedIn content and RevOps, alone or as one package, on flat retainers. Its home page names a pod of senior operators, at least a GTM engineer, an operations manager and a paid-media strategist. It reports named results with exact figures, for example $3,652,185 of Google-influenced pipeline for Doppel, and says it serves 150 or more B2B clients.

• Strengths: The same four services as ours under one pod, with exact figures on its home page. It states the client time it needs: a two to three hour intake, then biweekly sessions.
• Limits: The minimum term is six months, or four for smaller and earlier-stage companies. Its GTM page says clients do not need their own Clay license because it runs the work on its own table, and does not say who owns the tables afterward. Ask.
• Pricing: Not published; its pages say to book a call. Frontal's ranked list of GTM firms, updated 2026-10-21, prints $8,000 a month as a starting price. We did not find that figure on Understory's own pages.

Sources: Understory, GTM engineering page, Frontal's blog. Verified on 2026-10-28.

5. Growth Engine X: best for high-volume cold email with a free test first

Growth Engine X sells cold email: infrastructure, list building and campaign strategy, for B2B companies with $1M or more in revenue and a sales team in place. Its site offers a free test campaign to firms that qualify, and says that if it works, the two partner. Its Clay profile names Eric Nowoslawski, a former Clay employee, as founder.

• Strengths: A low-risk way to see results first. It says in public that domains, inboxes, Clay tables and lists are transferable to you.
• Limits: Email only, with no ads, content or CRM program. It says it is usually not a fit under 40,000 contacts or without a sales system.
• Pricing: Not published. Clay's directory shows no price and a three-month minimum.

Sources: Growth Engine X, Clay directory profile. Verified on 2026-10-28.

6. RevPartners: best for a HubSpot-centered team that wants prices up front

RevPartners offers RevOps as a service, GTM engineering as a service, Clay implementations and HubSpot onboarding and migrations. It says it holds Elite status with both HubSpot and Clay, and cites more than 1,000 CRM and RevOps deployments and more than 525 five-star HubSpot reviews.

• Strengths: The only full price list in this comparison, on its own pricing page. Deep HubSpot experience.
• Limits: It states no ownership terms for the work. Services are bought in hours-capped tiers, and the listed services center on RevOps, GTM engineering and Clay builds rather than ads or content.
• Pricing: GTM engineering is $12,900 to $24,000 a month across four tiers of 60 to 120 hours. RevOps is $9,850 to $27,000 a month with a six-month initial term and a $5,000 onboarding fee. A Clay implementation is $25,000 one time, launched in 90 days.

Sources: RevPartners, pricing page. Verified on 2026-10-28.

7. WarmUp: best for a team that wants to own the system at the end

WarmUp builds GTM engineering, paid media, LinkedIn content and RevOps as one system, in your own Clay, CRM and ad accounts. Outbound is built on signals, enriched in Clay and synced to HubSpot or Salesforce. We run it with your team until the numbers hold, then move the tables, plays, documents and numbers to a person you name, with training. Read the method and the GTM engineering page.

• Strengths: Ownership is the design: everything is documented as it is built and moves to you. The first version is live by week four, and the client time is stated, a thirty-minute review every two weeks. One cleared client result is on the record: Coya, 10 to 20 qualified meetings a week at peak and more than 100 leads a month from cold outbound.
• Limits: We publish no price and no minimum term. Three of our four services carry no cleared client result yet, and the cleared figures we hold are for a single client.
• Pricing: Pricing set on the first call.

Sources: our GTM engineering, paid media, LinkedIn content and RevOps pages. Checked on 2026-10-28.

Which one fits your situation?

The right firm depends on who should run the system on day 200, how much you want to spend before you see results, and which channels you need. These five cases cover most buyers at this stage.

• You want outbound, ads, content and RevOps from one team on a written scope: Frontal. If you would rather start with a 90-day pilot, Growth Today.
• You have a strong RevOps lead and an unusual setup that needs a custom Clay build: The Kiln.
• You want one named pod across four channels and can commit for six months: Understory.
• Your problem is the volume of cold email, you have a sales team, and you want to test first: Growth Engine X.
• HubSpot is your center and you want a price list before a call: RevPartners.
• You want the Clay tables, ad accounts and documentation in your name, and someone on your team running them: WarmUp. If you want a large outsourced team to run everything, or a published monthly fee, one of the others above fits better.

So which should you choose?

On the six public criteria, Frontal and Growth Today lead because they meet all six. The Kiln follows on five, and RevPartners is the one to call if a printed price list matters most. WarmUp ranks last because we publish no price or minimum term and have cleared figures for one client. We fit buyers who weigh ownership above all, and we do not fit buyers who want a published fee or a long track record of cleared results today.

Whichever you choose, ask the same three questions: who holds the accounts at the end, what the minimum term is, and which named client you can call.

Corrections: if a firm on this list finds an error, tell us and we will fix it and note the change here with the date.