Vendor offboarding checklist for leaving a marketing supplier

Aug 22
4 min read

Updated: 2 days ago

Introduction

The end of a supplier relationship is when leverage is highest and attention is lowest. Everyone wants it over, so the difficult items get skipped.

Those items — account ownership, data, documentation — are exactly what determines whether you keep anything of value from the engagement. Retrieving them afterwards is much harder and sometimes impossible.

1. A vendor offboarding checklist should be written at the start

The best time to agree what happens at the end is before the work begins, when both parties are cooperative.

Put it in the initial agreement: on termination, the client receives administrator access to all accounts, an export of all data, copies of creative files in editable form, and a written handover document.

Doing this at the outset costs a paragraph. Doing it at the end is a negotiation you may lose.

2. Reclaim account ownership before the final payment

The final invoice is the only real leverage you have. Use it deliberately and fairly.

Work through every platform and confirm you hold administrator rights from a business-owned email address: advertising accounts, analytics, the domain, hosting, the website admin, email sending, social profiles, listings, review platforms.

Where an account was created inside the supplier's own structure, ask specifically for a transfer rather than continued access. Access can be revoked; ownership cannot.

3. Export the data, and check the export opens

Data has a habit of being unavailable a week after access ends.

Export the customer and subscriber lists, historical performance data, form submissions, and any reporting history. Then open each file and confirm it contains what you expected — an export that completed and produced an empty or truncated file is common and easy to miss.

Store the exports somewhere in the business, not on the laptop of whoever downloaded them.

4. Get editable files, not just published output

A finished advertisement is not the same as the file it was made from.

Ask for layered design files, video project files, fonts and licences, photographs at full resolution, and the source documents for anything written. Published exports cannot be edited or resized without starting again.

Also ask which fonts and stock assets are licensed and whether the licence transfers. Often it does not, which is worth knowing before you reuse the material.

5. Insist on a written handover document

The most valuable and most frequently skipped item.

It should state: what is currently running and where, what the settings and reasoning are, what was tried and did not work, which routines happen on what schedule, what is scheduled to occur after they leave, and what needs immediate attention.

The reasoning is the part that matters. Any competent successor can see the current configuration; only the outgoing supplier can explain why it is that way.

6. Find out what will break, and when

Some things stop working after a supplier leaves, and not always immediately.

Ask directly: which tools are on their subscriptions, which automations run through their systems, which integrations authenticate with their accounts, and what is scheduled to renew or expire.

Then check for anything running under their connected app authorisations. These often keep working for a while and then fail without explanation, which is a difficult problem to diagnose months later.

7. Revoke their access on the agreed date, methodically

Once handover is complete, remove access properly — not as a gesture of distrust but as ordinary hygiene.

Remove their user accounts across every platform, change any credentials that were shared rather than individually assigned, revoke connected application permissions, and confirm every registered email address is one you control.

Leaving old supplier access in place is how businesses accumulate a dozen former agencies with live administrator rights.

8. Debrief internally and record the lesson

Once it is finished, write half a page for your own use.

What the engagement produced, what it cost, what worked, what you would specify differently, and which items on this list were difficult to obtain. That last point is the most useful, because it tells you exactly what to put in the next contract.

Keep it with the handover document. A business that has offboarded two suppliers well has better contracts than one that has never had to.

Conclusion

Write the offboarding terms into the original agreement, then use the final payment as the moment to confirm account ownership rather than mere access.

Export and verify all data, obtain editable source files with their licences, insist on a written handover explaining reasoning as well as configuration, establish what will break and when, revoke access methodically on the agreed date, and record what was hard to get so the next contract covers it.