Most practices run five or six layers of software: a ledger, practice management, proposals and engagement letters, fee billing, collection and chasing. An integration between two of them is worth having when it removes a step somebody types, matches payments to invoices without anyone opening the ledger, and keeps working when a client changes something at their end. For your own fees, the joins that save the most time are usually between engagement, collection and the ledger.
In this article
The short version
- Most practices run five or six layers of software, from the ledger to collection and chasing.
- An integration earns its place if it removes typing, matches payments on its own and survives client changes.
- Decide once which system owns your fee notes to stop the same fee living in two places.
- Run five real transactions through any trial, including a part payment and a failed collection.
- "MTD-compatible" tells you what a product can file, not how anyone gets paid.
The layers in a practice's stack
Sketch your stack on paper and you'll usually find more boxes than you expected.
| Layer | What it holds | Whose subscription it usually is |
|---|---|---|
| Ledger | Transactions, VAT returns and MTD filings | Your client's, sometimes yours on their behalf |
| Practice management | Client records, jobs, deadlines, AML checks | Yours |
| Proposals and engagement | Price, scope and signature | Yours |
| Fee billing | Your own fee notes | Whichever product you raise them in |
| Collection | Mandates, card and bank payments, payouts | Yours for your fees, your client's for theirs |
| Chasing | Reminders and follow-up | Whichever product holds the invoice |
Duplication tends to creep in at fee billing. If practice management raises the fee note and the ledger holds a copy, someone keeps the two in step by hand. Decide once which system owns the fee note and which one only holds a copy, and you'll remove more admin than most integrations do.
Your own fees and your clients' receivables are also different jobs. When you help a client with their debtors, you're working in their ledger, on their subscription, with their name on the reminder. When you collect your own fees, you're the biller. Vendor pages rarely say which of the two they mean, so on a demo, ask whose invoice gets chased and whose account the money lands in.
Don't read too much into "MTD-compatible" on a product page. It means the product can keep digital records and file to HMRC, and HMRC's software criteria say nothing about invoicing or collecting payment.
Four tests for any integration
Integrations pages run long because a logo is easy to add. Four questions tell you whether an integration will change your week:
- Does it remove a step somebody types? If a fee note raised once appears everywhere else on its own, you'll see the saving in your timesheets. If someone still exports a spreadsheet every month, it hasn't removed that step.
- Does it match payments to invoices without anyone opening the ledger? Full marks means a part payment, an overpayment and a transfer with no reference all land on the right invoice. Half marks means the money shows up in the bank feed and a person allocates it.
- Does it cope with changes at the client's end? Invoices get edited after they're issued, voided and reissued, or paid straight into the bank instead of through the link. Ask what each of those does to a reminder that's already scheduled.
- Does it tell somebody when it breaks? A sync that stops without warning can do more harm than no sync, because you'll trust the numbers until someone notices they're wrong.
Built-in ledger reminders show why the third test matters. Xero's reminders only stop when a payment arrives if the bank feed is connected and the payment's been reconciled, they only go out on invoices marked as sent, and the setting to ignore small balances applies to every invoice at once. Neither Xero's nor QuickBooks' built-in reminders have any notion of a payment plan, a dispute or a failed payment. If your invoices often get part paid or queried, whatever chases them needs to know more than the ledger does.
What to put through a trial
A demo shows you the happy path. Five transactions, run through a trial with one friendly client, show you the product:
- A part payment. Does the reminder stop, change or carry on asking for the full amount?
- An invoice edited after it's issued. Does the new amount reach the reminder and the payment link?
- A payment made straight into your bank. Does the invoice close by itself, and how quickly?
- A failed collection. Who's told, what's retried and what does the client see?
- A fee note raised in practice management. Does it reach the ledger without being typed twice?
While you're at it, check where client replies to reminders go. In some setups they land in the inbox of whoever switched reminders on, which can mean a partner's inbox where nobody else sees them. Decide which inbox should get them before you go live.
Where collecting your own fees fits
For your own fees, the biggest saving tends to come from linking three layers: the engagement letter where the fee is agreed, the collection that takes the money, and the ledger where it's recorded. When those are joined, a client agrees the fee and signs a direct debit mandate in one step, each fee is collected on its due date and the payment is matched to the invoice without anyone touching it.
Adfin works in that layer. It has a two-way sync with Xero and QuickBooks, so invoices come in and payments go back against the right invoice, including part payments and transfers with missing references. It also integrates with the practice tools Socket, Engager.app and Sodium, so a client can set up their direct debit as part of accepting your proposal or engagement letter. For anything that goes unpaid, Adfin's AI Customer Agents chase over email, SMS and WhatsApp from your own email domain, within rules you set.
Whichever tools you choose, check an integration with both vendors, not only the one whose page you're reading, and run the five trial transactions before you move your whole book across.
Common questions
What software does an accountancy practice need as a minimum? A ledger for the compliance work, somewhere to hold client records and deadlines, and a way to raise and collect your own fees. Everything else combines or extends those three.
Does MTD-compatible software handle invoicing or payments? Not as part of being compatible. HMRC's criteria cover digital records, quarterly updates and the tax return, with nothing on invoicing or collecting payment.
What's the difference between a one-way and a two-way sync? One-way sends information in one direction only, so a change at the far end never comes back and someone fixes it by hand. Two-way means a payment recorded in the collection tool appears against the invoice in the ledger, and changes in the ledger reach the collection tool.
What breaks an accounting integration most often? Changes the integration wasn't told about: an invoice edited or voided after issue, a new invoice number for the same work, an out-of-date contact email, or a payment made straight into the bank.
Should a practice raise fee notes in the ledger or in practice management? Either works, as long as you pick one as the master record. Practice management knows the job and scope, while the ledger holds VAT and the audit trail.
Which practice tools does Adfin integrate with? Xero and QuickBooks with a two-way sync, and the practice tools Socket, Engager.app and Sodium for signing a direct debit mandate with the proposal or engagement letter.
Sources
- HMRC - Find software that's compatible with Making Tax Digital for Income Tax (accurate as of October 2026) https://www.gov.uk/guidance/find-software-thats-compatible-with-making-tax-digital-for-income-tax
- Xero Central - Set up invoice reminders (accurate as of October 2026) https://central.xero.com/s/article/Set-up-invoice-reminders
- Intuit QuickBooks UK - Send invoice reminders automatically or manually (accurate as of October 2026) https://quickbooks.intuit.com/learn-support/en-uk/help-article/invoicing/send-invoice-reminders-automatically-manually/L84cQjpxo_GB_en_GB
- Adfin - Adfin for Engager.app (accurate as of October 2026) https://www.adfin.com/integrations/engager-app
- Adfin - Payments and credit control for accountants (accurate as of October 2026) https://www.adfin.com/accountants
