How to Choose a HubSpot Integration Partner: A UK Buyer's Checklist

Choosing the wrong HubSpot integration partner is expensive twice: once when the project drags, and again when the thing they built breaks quietly a year later and nobody owns it. This checklist sets out what actually separates integration partners, the questions that expose the differences, and the red flags we see in rescue projects.

1. Who actually writes the code?

Many agencies sell integrations and then outsource the engineering, or assemble no-code middleware and call it a build. Both models fail the same way: when something breaks, the people you hired cannot fix it. Ask directly: are the engineers employed in-house? Can we meet the person who will write our integration? Who maintains it after go-live? At SpotDev the people who scope the work are the engineers who build and support it, and we treat that as the single most important structural question a buyer can ask.

2. Accreditation and tier, decoded

HubSpot's partner programme has tiers (Gold, Platinum, Diamond, Elite) based on delivery and customer success, and separately it has accreditations, which are audited capability reviews. The one that matters for this decision is the Custom Integration Accreditation: HubSpot examines a partner's actual integration architecture, code quality and delivery process before granting it. A tier tells you a partner sells a lot of HubSpot; the accreditation tells you HubSpot has audited how they build. Our guide to HubSpot partner tiers explains the system in full.

3. How is it priced?

Day rates put all the scope risk on you. A partner who scopes properly can quote a fixed price and stand behind it; a partner who cannot is telling you their discovery process does not de-risk the work. Ask for a fixed price, ask what is excluded, and ask what happens if they miss the date. We quote fixed prices from £5,000 with a delivery guarantee, and we publish our approach on our HubSpot integration services page precisely because so few firms will put numbers in writing.

4. What happens after go-live?

Integrations are not finished when they ship; APIs change, auth tokens expire, volumes grow and someone will eventually rename a property. The question that separates real engineering firms from project shops is: who is watching it, and what is the plan when it breaks? Look for monitoring and alerting as standard, documentation you could hand to another developer, and a named support arrangement. Our view on this is in when your integration breaks.

5. Security posture

Your integration partner will hold credentials to your CRM and probably your finance system. Ask about Cyber Essentials Plus or equivalent certification, data processing agreements, how credentials are stored, and whether data passes through or rests in any third-party middleware. A partner who cannot answer quickly has not been asked before, which is its own answer. The full picture is in our guide to HubSpot integration security and UK GDPR.

6. Proof, not promises

Ask for named case studies with specifics, and read the partner's reviews on the HubSpot Solutions Directory, where only verified customers can post. SpotDev's listing shows a 5.0 rating across 38 reviews on the HubSpot Solutions Directory, and our case studies name the clients and the outcomes.

The red flags

In rescue projects, the same patterns recur: no written scope before a price; "we will use middleware" as the answer to every requirement; no QA or test plan; no documentation; the salesperson cannot introduce an engineer; and no answer to "who supports this in year two". Any one of these is survivable. Two or more is a prediction.

Ten questions to take into the call

1. Who writes the code, and are they employed by you?
2. Are you HubSpot Custom Integration Accredited?
3. What is the fixed price, and what is excluded?
4. What happens if you miss the delivery date?
5. How will we know when the integration fails?
6. Who fixes it, and how fast?
7. What documentation do we receive?
8. What security certification do you hold?
9. Where does our data rest in transit?
10. Can we speak to a customer with a similar system?

Frequently asked questions

What accreditation should a HubSpot integration partner have?

Look for HubSpot's Custom Integration Accreditation, an audited review of a partner's integration architecture, code quality and delivery process. Partner tier (Gold to Elite) measures scale of delivery; the accreditation measures how they build.

Should a HubSpot integration be fixed price?

Usually, yes. A partner who scopes properly can commit to a fixed price and a date. Day-rate-only pricing moves all scope risk onto you, and it removes the partner's incentive to finish.

How do I verify a HubSpot partner's reviews?

Check their listing on the HubSpot Solutions Directory, where reviews come from verified customers, and ask for named case studies with concrete outcomes rather than anonymised claims.

Evaluating partners now? Start with the complete guide to connecting anything to HubSpot, then put our answers to the ten questions to the test: custom HubSpot integration services, fixed price, built by in-house engineers.