Most subscription system migrations go fine on the day. The live subscribers come across, the counts match and the first issue goes out.
The trouble turns up later. The auditor asks when a reader requested the title, and the answer is the date of the import. Finance asks about a payment from two years ago, and it's in a system nobody has a login for any more. A reader who opted out in 2023 gets a marketing email, because their opt-out didn't make the trip.
So the real job isn't moving subscribers. It's moving the history behind them, whichever system you're moving to.
Decide what "history" means for you
Start with a list, not a data dump. For most publishers the history that matters falls into five groups:
- Circulation evidence. Request and qualification dates, sources, methods and answers for every controlled reader.
- Orders and payments. Every subscription term, invoice, payment, refund and credit, not just the current one.
- Consent and objections. Who agreed to what, when and how, and who said no.
- Renewal and contact history. Which reminders and renewal efforts went out, and when.
- Service history. Missed copies, complaints, address changes and notes.
For each group, write down where it lives today, whether it's coming across in full, in summary or not at all, and who has signed that off. That last column saves arguments later.
What the auditor will want
If you're ABC audited, this is the part to get right. ABC's Business Magazines Reporting Standards say the date of each request must be recorded so it can be analysed by age. Evidence for a controlled copy has to be less than five years old on the date you send it, a limit that has been five years since 2018 (it was three before).
The classic migration mistake is an import that stamps every record with the day it was loaded. On paper, your whole file suddenly looks freshly requested. That's wrong, and an auditor will spot it when the evidence doesn't match. Bring the original request date, source and method across as data, not as a note in a free-text field.
ABC also wants records kept until it has finished auditing the following corresponding period, and you must be able to recreate the mailing list for any issue in the period. Business magazine certificates have run January to December since 2025. So if you switch in, say, June, the first half of the year's lists live in the old system. Either bring the issue-by-issue mailing history across, or make sure you can still get at it until that audit is closed.
If you're with AAM (formerly BPA), the clock is 36 months rather than five years, but the point is the same: the request date is evidence, so it has to survive the move.
What finance will want
Subscription orders and payments are accounting records. GOV.UK says a company must keep its accounting records for 6 years from the end of the last financial year they relate to, and HMRC's VAT record keeping notice says VAT records must be kept for at least 6 years.
That doesn't mean every old invoice has to be live in the new system. It does mean someone has to be able to find it. A read-only archive of the old system, or a full export that finance has checked they can actually use, is fine. A backup file nobody can open isn't.
Watch deferred revenue in particular. Subscriptions paid upfront and part-delivered on migration day need their remaining issues and value brought across exactly, or your first month-end will be a puzzle. Run a closed month through both systems and compare before you trust the new one.
Consent and objections
The ICO's guidance on recording consent expects you to show who consented, when, how, what they were told and whether they've since withdrawn. A single "opted in: yes" field doesn't do that. Migrate the dated history, not just the current status.
Objections matter even more. Under the ICO's right to object guidance, the right to object to direct marketing is absolute, and it's usually better to suppress someone's details than delete them. Your suppression list must come across in full, including people who are no longer subscribers. It's very easy to leave those behind because they don't look "live".
Renewals, reminders and the January rules
Move each subscriber's start date, current term, price and renewal method exactly. Get the start date wrong and renewals fire at the wrong time. Get the renewal method wrong and someone paying by Direct Debit gets an invoice, or the other way round.
The timing matters this year too. The new consumer subscription rules are due to apply to auto-renewing contracts entered into from 1 January 2027, though the regulations still need Parliament's approval. Your records need to show when each contract really started, so the import date mustn't stand in for it. Our guide to the subscription rules covers what changes.
If you collect by Direct Debit and the collection arrangements are changing, talk to your bank or Direct Debit bureau early. Mandates are the one thing you really don't want readers to have to set up again.
Pick your moment
There's no perfect day to switch, but there are bad ones. Avoid the run-up to your ABC Audit Issue, which for a January to December title is normally the early December issue. Avoid your busiest renewal month and the weeks before a financial year-end.
It's worth doing a trial migration first: check it, fix what's wrong and then do the real one. If you can, run both systems side by side for an issue and compare the mailing files. Differences you find then are cheap. Differences you find at audit aren't.
Check before you switch off
Before the old system goes, check:
- Live counts per title and per circulation category match.
- Request age bands look the same in both systems, not suddenly all under a year.
- A closed month's deferred revenue, debtors and VAT agree.
- Suppressions and opt-outs match in number.
- A sample of real readers, checked by hand, record by record.
Then keep read-only access to the old system, or a usable export, for as long as your retention schedule says.
Where we fit in
If you move to Avio, our subscription platform for larger publishers, we do the heavy lifting on the migration and check the results with you. When our circulation and subscriptions bureau takes over a file, subscribers, order history and Direct Debit details come across and we check the counts with you. If you'd like a tidy-up before you move anywhere, our team can do a one-off data clean. And if you're still choosing, our comparison of subscription software is a good place to start.
If a migration is on the cards and you'd like a second pair of eyes on the plan, get in touch.
Rob Sherwood is Managing Director of Adept Data Services. He has spent his career in subscriptions and circulation, at WDIS, Optima and CDS Global before founding Adept.