Xero vs. FreeAgent vs. Sage vs. QuickBooks: Credit Control Compared

If you're automating invoice chasing, “sync my overdue invoices” means something different depending on which accounting platform you're on — some platforms have an explicit “Overdue” status; others require you to work it out yourself from the due date and outstanding balance. Here's how the four major UK platforms actually differ, based on building direct integrations with all of them.

FreeAgent

FreeAgent has the most explicit model: every invoice carries a status field with a fixed set of values — Draft, Scheduled To Email, Open, Overdue, Paid, and a few others. Critically, an invoice only becomes Overdue once it has actually been marked Sent and its due date has passed — a draft invoice with a due date in the past stays Draft, it never auto-promotes to overdue. FreeAgent's API accepts a view=overdue query parameter that returns exactly this — no client-side date math required.

Xero

Xero doesn't have a distinct “overdue” status at all. Invoices have a Status (DRAFT, AUTHORISED, PAID, etc.) and an AmountDue, but whether an authorised, unpaid invoice counts as overdue is purely a function of its due date versus today — Xero leaves that computation to whoever's consuming the API. In practice this means querying for Status=="AUTHORISED" AND AmountDue>0 and then filtering by due date yourself, rather than asking Xero directly for “overdue” invoices.

Sage (Sage Business Cloud Accounting)

Sage's sales invoice records expose a due date and an outstanding balance, but — unlike FreeAgent — there's no dedicated overdue-only filter parameter in the invoices list endpoint. The reliable approach is the same as Xero's: pull invoices with an outstanding balance, then compute overdue-ness client-side from the due date, rather than trusting a platform-side “overdue” flag.

QuickBooks Online

QuickBooks Online uses a SQL-like query language over its API (SELECT * FROM Invoice WHERE Balance > '0'), which is powerful but, like Xero and Sage, doesn't have a built-in “overdue” concept — Balance > 0 gets you everything unpaid, sent or not, due or not, and the due-date comparison is on you.

Why this matters if you're evaluating tools

If a credit-control tool advertises “real-time sync with your overdue invoices,” it's worth knowing that on three of these four platforms, “overdue” isn't something the accounting platform tells the tool directly — it's something the tool has to correctly compute itself from due dates and balances, invoice by invoice. FreeAgent is the outlier in doing this natively. It's a small technical detail, but it's exactly the kind of thing that produces subtly wrong results (invoices chased too early, or missed entirely) if a tool's integration gets it wrong.