Ignition

Ignition fixes the commercial side of a practice: agreeing scope and price up front, getting the engagement letter signed, and making sure the firm actually bills and collects what was agreed. For many UK firms it is the tool that ended month-end invoicing runs and awkward fee chasing.

What it does well. The proposal to payment chain is tight. Once a client accepts, billing runs on schedule, payment is collected and the receipt lands reconciled in Xero or QuickBooks, which removes a whole category of admin and write-offs. UK support is real, with sterling pricing, Sage and Xero Practice Manager integrations and a Karbon link for workflow. Recognition as Xero's Global Practice App of the Year 2026 reflects its standing in the Xero ecosystem. Price Insights and AI-built proposals help firms price more consistently, and the company's stress on the accountant staying in control of AI drafts is the right tone.

Where it falls short. Cost adds up. Plans are tiered by firm size and active clients, add-ons such as the deals pipeline are around £39 a month each, and card payment fees apply on top. Firms should model the all-in cost for their client count before the 14-day trial ends. The AI pricing benchmarks rely on Ignition's own customer data, so treat them as a guide, not market evidence. Moving every client onto Ignition's engagement and payment flow is a real change project, and once billing and payment data live there, switching is painful. Reported outcomes on late payment and scope creep come from the company.

Best for. UK and international practices on Xero or QuickBooks that want fixed-fee packaging, signed engagement letters and automated collection in one place. Very small firms with a handful of clients may manage with their ledger's invoicing and an e-signature tool, and firms wanting full practice management alongside billing should pair it with Karbon or compare Financial Cents in this directory. In a trial, migrate ten real clients and check how direct debit, card fees and failed payments are handled.

Verdict. The leading proposals and billing platform for Xero-based practices, with useful AI on pricing and strong UK support. Worth the cost for firms that struggle to bill and collect consistently; check the all-in price, including add-ons and payment fees, first.