Free MTD VAT Bridging Software for Spreadsheet Users
Since April 2019, HMRC has required all VAT-registered businesses above the VAT threshold to submit their VAT returns digitally through Making Tax Digital (MTD). Since April 2022, this requirement extends to all VAT-registered businesses regardless of turnover. For businesses that keep their records in spreadsheets, this means you need bridging software to create the digital link between your spreadsheet and HMRC. DIY Accounting provides this service for free.
What Is Bridging Software?
Bridging software is a tool that takes information from a non-MTD system (such as a spreadsheet) and submits it to HMRC through the Making Tax Digital API. HMRC recognises bridging software as a valid way to meet MTD obligations, as confirmed in their list of compatible software.
The bridging software handles the technical communication with HMRC's systems. It authenticates you via your Government Gateway credentials, retrieves your outstanding VAT obligations, accepts your nine-box VAT return figures, and submits them digitally to HMRC. You receive a confirmation receipt with a unique reference number.
Why Spreadsheet Users Need Bridging Software
HMRC does not provide its own online portal for MTD VAT submissions. The old manual submission through the HMRC website is no longer available for businesses that must comply with MTD. According to HMRC's guidance on keeping VAT records, you can continue to use spreadsheets for your day-to-day record-keeping, but you must use MTD-compatible software for the actual submission of the VAT return.
This means that even though your DIY Accounting spreadsheet correctly calculates all nine boxes of the VAT return, you cannot simply type those figures into an HMRC web form. You need a piece of software that provides the "digital link" to transmit the data to HMRC's API.
DIY Accounting's Free Submission Service
DIY Accounting provides a free MTD VAT bridging service at submit.diyaccounting.co.uk. This web-based service is listed by HMRC as compatible software for Making Tax Digital for VAT. Here is how it works:
- Sign in with Government Gateway. The service uses HMRC's OAuth 2.0 authentication, so your Government Gateway credentials are entered directly on HMRC's website. DIY Accounting never sees your password.
- View your obligations. The service retrieves your outstanding VAT return periods directly from HMRC, so you can see exactly which periods need to be submitted.
- Enter your VAT figures. Transfer the nine-box VAT return figures from your DIY Accounting spreadsheet into the submission form.
- Submit and receive confirmation. After you confirm the legal declaration, your return is submitted to HMRC and you receive a receipt with a reference number for your records.
Using DIY Accounting Spreadsheets with the Submission Service
The DIY Accounting spreadsheet packages for VAT-registered businesses (Self Employed and Company Limited) include a VAT calculation sheet that automatically totals your VAT figures for each period. The workflow is straightforward:
- Record your sales and purchases in the spreadsheet throughout the VAT period.
- At the end of the period, check the VAT calculation sheet for your nine-box totals.
- Visit submit.diyaccounting.co.uk, sign in, and select the relevant VAT period.
- Enter the nine-box values from your spreadsheet.
- Review, confirm, and submit.
The entire submission process typically takes just a few minutes once your spreadsheet figures are ready.
Advantages of Using a Free Bridging Service
- No cost. The DIY Accounting submission service is completely free. There are no subscription fees, per-submission charges, or hidden costs.
- Keep your existing workflow. You do not need to change how you keep your records. Continue using your DIY Accounting spreadsheet and simply use the bridging service for the final submission step.
- Secure. Authentication is handled directly by HMRC's Government Gateway. The service connects to HMRC's official MTD API and does not store your VAT return data after submission.
- No software to install. The service runs in your web browser. There is nothing to download, install, or update.
Alternatives to Bridging Software
If you prefer not to use bridging software, the alternative is to move all your bookkeeping into full MTD-compatible accounting software that handles both record-keeping and submission. However, many small business owners prefer the flexibility and familiarity of spreadsheets, making bridging software the practical choice.
Article generated by Claude Code for DIY Accounting, February 2026. All information sourced from GOV.UK and HMRC guidance linked inline.
Tax reference: MTD VAT bridging software – Source: GOV.UK: Find software compatible with Making Tax Digital for VAT (applicable tax year 2025/26)