Since April 2022 every VAT-registered UK business must keep digital records and submit VAT returns through HMRC's Making Tax Digital (MTD) API — manual keying into the HMRC portal is closed. ERPNext gives you accurate VAT accounting and a nine-box picture of your liability, but it has no native OAuth 2.0 connection to HMRC, no fraud-prevention header handling, and no obligations/liabilities/payments retrieval. That gap is where UK finance teams end up copying figures into third-party bridging spreadsheets, breaking the digital link HMRC requires.

We build a proper Frappe app (its own module, installed on your bench via bench get-app and bench install-app) that closes the loop end to end. A custom HMRC VAT Return DocType maps directly onto ERPNext's VAT-boxed tax accounts, computing all nine boxes from your posted Sales Invoice, Purchase Invoice, and Journal Entry data for the selected obligation period. Whitelisted server methods (@frappe.whitelist()) drive the HMRC VAT (MTD) endpoints — retrieve open obligations, submit the return, and read back liabilities and payments — over OAuth 2.0 with encrypted token storage and automatic refresh. Every request carries the mandatory Gov-Client- and Gov-Vendor- fraud-prevention headers HMRC now enforces, assembled server-side and from a lightweight client script so submissions aren't rejected.

The app ships UK localization as installable fixtures: standard (20%), reduced (5%), and zero-rated VAT tax templates and a Sales/Purchase Taxes and Charges rate table, plus a UK chart of accounts and a VAT control account structure that reconciles to the nine boxes. Where you operate under the Construction Industry Scheme, we add CIS deduction handling — a contractor/subcontractor flag on suppliers, CIS deduction accounts, and calculation logic wired into purchase transactions via hooks.py doc events so the deduction is captured at source and reported cleanly. A dedicated MTD VAT Settings single DocType holds your VRN, HMRC client credentials, and environment toggle (sandbox vs. production), and a scheduler event polls for approaching obligation deadlines so nothing is missed.

Because this is build-to-order, nothing is downloaded from a marketplace and switched on blind. After a short scoping call we confirm your ERPNext version (v15 or v16), your VAT scheme (standard, flat-rate, cash accounting), whether CIS applies, and your existing account mappings. We build against that scope, test the full submit flow against HMRC's sandbox, deploy to a staging bench for your UAT, and only then cut over to production with a rollback plan. You receive the full source, a git repository handover, documentation, a training session, and a post-go-live support window. Typical delivery is 2–4 weeks from confirmed scope.