Bridging Software for MTD Income Tax

MTD Bridging Software: How to Submit Quarterly Updates from a Spreadsheet

Last updated: February 2026

Not everyone wants to abandon their spreadsheet. If you have been tracking self-employment or rental income in Excel for years and your records are thorough, Making Tax Digital does not force you onto a cloud accounting platform. Bridging software offers another route: it connects your existing spreadsheet to HMRC’s systems, extracting the summary totals and submitting them as quarterly updates. You keep your records exactly where they are.

This guide explains how bridging software works, what HMRC requires for the digital link, and which tools are recognised for MTD for Income Tax. It also walks through the step-by-step process of submitting a quarterly update using VitalTax, one of the most popular bridging tools.

What bridging software actually does

Bridging software sits between your spreadsheet and HMRC. It does not replace your record-keeping. It does not categorise transactions, pull in bank feeds, or generate invoices. Its sole job is to take the figures from your spreadsheet and submit them to HMRC through the MTD API in the correct format.

Full accounting software such as Xero or FreeAgent is different. Those platforms handle everything: you enter transactions (or import them via bank feeds), the software categorises them, generates reports, and submits to HMRC from within the same system. With bridging software, the record-keeping stays your responsibility. The bridging tool only handles the last step: transmission.

Think of it this way. Full accounting software is the entire postal service, from writing the letter to delivering it. Bridging software is just the postbox. You still write, address, and stamp the letter yourself.

The digital link requirement

HMRC requires a digital link between your records and the data submitted to them. This means figures must flow electronically from your spreadsheet into the bridging tool without manual retyping at any point in the chain.

What counts as a digital link:

• An Excel add-in (such as VitalTax) that reads cell values directly from your workbook
• A CSV export from your spreadsheet imported into a bridging application
• A pre-formatted template where your figures feed through formulas to submission-ready cells

What does not count:

• Reading totals off a paper printout and typing them into the bridging tool
• Copying figures from a handwritten notebook into Excel and then submitting
• Manually entering numbers from memory into any software

The rule is straightforward. If a human had to look at one screen and retype a number into another, the digital link is broken. The data must move from your records to HMRC through an unbroken electronic chain. HMRC’s guidance on digital links (written for VAT but applying the same principles to income tax) makes this point repeatedly.

HMRC-recognised bridging tools for MTD ITSA

HMRC maintains a list of MTD-compatible software for MTD Income Tax. The following bridging tools appear on that list and are designed specifically for people who want to keep using spreadsheets.

VitalTax (£30 + VAT per year)

VitalTax installs as an Excel add-in. You map cells in your existing spreadsheet to the fields HMRC requires, and VitalTax reads those values when you submit. It supports sole trade income, UK property income, and foreign property income. The £30 + VAT price covers a single National Insurance number. Accountants and bookkeepers can buy an unlimited licence for £90 + VAT per year, covering all their clients.

VitalTax is the most widely discussed bridging tool in the MTD ITSA community and has been through HMRC’s pilot testing programme.

123 Sheets (£30 + VAT per year)

Rather than connecting to your existing spreadsheet, 123 Sheets provides its own pre-formatted Excel template. You enter your income and expenses into the template, and the built-in macros handle the submission to HMRC. This removes the need to map cells yourself but means adopting a new spreadsheet layout. For people who do not already have an elaborate spreadsheet, this is often simpler than VitalTax.

Forbes MTD (from £40 per year)

Forbes MTD is a standalone Windows application rather than an Excel add-in. You export your spreadsheet data as a CSV file and import it into Forbes MTD, which then submits to HMRC. This approach works with any spreadsheet application, not just Excel. The trade-off is the extra step of exporting and importing each quarter, though the process takes only a few minutes.

TaxCalc (from £75 per year)

TaxCalc is desktop software that handles Self Assessment returns and MTD quarterly updates. It includes a bridging function that imports data from spreadsheets, but it also offers its own bookkeeping features. At £75 per year, it costs more than the pure bridging tools, but you get a fuller package that can also prepare your final declaration (replacing the annual tax return) and Self Assessment return. For someone who wants one tool covering both quarterly updates and year-end filing, TaxCalc bridges the gap between simple bridging software and full accounting platforms.

Step-by-step: submitting a quarterly update via VitalTax

Here is the practical workflow for submitting a Quarter 1 (6 April to 5 July) update using VitalTax with an existing Excel workbook.

Step 1: Prepare your spreadsheet. Make sure your income and expense records for the quarter are complete. You need summary totals for turnover (gross income), allowable expenses broken down by category (such as travel, office costs, phone, professional fees), and any capital allowances claimed. Each figure should sit in its own clearly labelled cell.

Step 2: Open the VitalTax add-in. In Excel, go to the VitalTax ribbon tab. If this is your first submission, you will need to enter your Government Gateway credentials and authorise VitalTax to submit on your behalf. This authorisation lasts 18 months before needing renewal.

Step 3: Map your cells. VitalTax presents a list of HMRC submission fields: turnover, cost of goods sold, repairs, travel, office supplies, and so on. For each field, you click the corresponding cell in your spreadsheet. VitalTax remembers these mappings, so you only do this once. For subsequent quarters, the same cells are read automatically (assuming your spreadsheet layout stays consistent).

Step 4: Review the summary. VitalTax displays the figures it has read from your spreadsheet alongside the HMRC field names. Check every number matches what you expect. This is your last chance to spot errors before submission.

Step 5: Submit. Click the submit button. VitalTax sends the data to HMRC’s MTD API and returns a confirmation with a receipt number. Save this receipt. The quarterly update for Q1 is due by 7 August, so make sure you complete this before the deadline.

The entire process, from opening VitalTax to receiving the confirmation, typically takes under ten minutes once your cell mappings are set up.

Who bridging software suits

Bridging software works best for a specific type of person. You are an experienced spreadsheet user with well-organised records. You have one or two income sources (a sole trade, a rental property, or both). You prefer to keep control of your own record-keeping rather than relying on cloud software. And you are cost-conscious: £30 to £75 per year is considerably cheaper than £84 to £180 per year for a full accounting platform.

Bridging also suits people who are already MTD-compliant for VAT using spreadsheets and want to follow the same approach for income tax. The workflow is almost identical.

Who should consider alternatives

Bridging software is not the right fit for everyone. If any of the following apply, a full accounting platform is likely a better choice.

• Multiple complex income sources. Managing three or four income streams in a spreadsheet and submitting each through a bridging tool quarterly is time-consuming and increases the risk of errors.
• You want your accountant to have access. Most accountants cannot log into your Excel file remotely. Cloud platforms like Xero let your accountant view, adjust, and submit on your behalf.
• You are not confident with spreadsheets. If your current records are disorganised, contain formula errors, or are missing months of data, bridging software will not fix those problems. It will simply submit whatever numbers it finds.
• You want bank feeds and automatic categorisation. These features only exist in full accounting software. With bridging, every transaction must be entered or downloaded manually.

If you prefer the structure and automation of full accounting software, our Xero team can advise on the best package for your situation.

Limitations to be aware of

Bridging software transmits data. It does not validate your records or tell you if something is wrong. If you enter £5,000 as turnover when the real figure is £50,000, the bridging tool will happily submit £5,000. There is no cross-check against your bank statements, no reconciliation, and no warning when figures look unusual.

You are also responsible for keeping your spreadsheet backed up and secure. HMRC requires you to preserve digital records for at least five years after the 31 January filing deadline for the relevant tax year. A lost or corrupted spreadsheet file could leave you unable to support a submitted return during an enquiry.

There is no automatic reminder system built into most bridging tools. You need to remember the quarterly deadlines yourself: 7 August, 7 November, 7 February, and 7 May. Miss one, and HMRC’s points-based penalty system adds a late submission point. Four points triggers a £200 fine.

Worked example: Emma, freelance translator

Emma is a self-employed translator based in Leeds. Her gross self-employment income for 2026/27 is £55,000, comfortably above the £50,000 threshold for Phase 1 of MTD ITSA starting in April 2026. She has no rental income.

Emma has tracked her income and expenses in a detailed Excel workbook for the past eight years. Every invoice is logged with the date, client name, amount, and payment date. Expenses are categorised by type: home office costs, professional subscriptions, software licences, travel, and professional development. Her spreadsheet contains formulas that calculate quarterly totals automatically.

Emma chooses VitalTax at £36 (including VAT) per year. She installs the Excel add-in and maps her quarterly summary cells to the HMRC fields. Her Q1 figures for 6 April to 5 July 2026:

Emma opens VitalTax, reviews the figures it has pulled from her spreadsheet, and submits her Q1 update on 28 July, well within the 7 August deadline. The whole process takes seven minutes. Her annual MTD compliance cost: £36. Had she chosen Xero Simple, the annual cost would have been £84 with the benefit of bank feeds and accountant access. For Emma, who is methodical and self-sufficient, the spreadsheet route is the better fit.

The important point is that Emma’s spreadsheet was already well-organised before MTD. Bridging software made compliance cheap and painless because her records were already in good shape. If her spreadsheet had been a mess, the tool would have submitted a mess.

Getting started

If you are confident your spreadsheet records are accurate and well-structured, bridging software offers the cheapest and least disruptive path to MTD compliance. Start by checking HMRC’s compatible software list to confirm your chosen tool is recognised, then set up your Government Gateway authorisation well before your first quarterly deadline.

Sources

• GOV.UK: Find software compatible with Making Tax Digital for Income Tax (for sole traders and landlords)
• GOV.UK: Use Making Tax Digital for Income Tax
• GOV.UK: VAT Notice 700/22 – Digital links