MTD Bridging Software Explained for Spreadsheet Users

Making Tax Digital (MTD) means that, if the rules apply to you, you keep digital records and send your figures to HMRC using software. That does not necessarily mean abandoning your spreadsheet. If you already track your income and expenses in Excel or Google Sheets, bridging software can connect that spreadsheet to HMRC. This guide explains what bridging software does, who it suits and where it can catch people out.

Key takeaways

• Bridging software lets a spreadsheet send its figures to HMRC securely, without retyping them into a web form.
• You still need to keep digital records and meet the digital link rules between any software you use.
• HMRC publishes a list of compatible software. Use it rather than relying on a provider's own claims.
• Bridging suits people with simple records. Full accounting software often saves time once you have many transactions.
• Whichever route you choose, set it up and test it well before your first quarterly update is due.

What is MTD bridging software?

Bridging software acts as a go-between. You keep your income and expenses in a spreadsheet. The bridging software reads the totals from that spreadsheet and submits them to HMRC through HMRC's official connection. It is called a "bridge" because it links two things that otherwise cannot talk to each other: your spreadsheet and HMRC's digital systems.

The spreadsheet remains your record. The bridging software does not usually replace it. It simply handles the authorised submission, and it normally receives HMRC's confirmation back, so you have proof that the update was sent.

Why bridging exists

Making Tax Digital for Income Tax applies in stages to self-employed people and landlords based on their qualifying income. Many of those people already use spreadsheets and prefer not to switch systems. HMRC allows spreadsheets as part of the process, provided the figures reach HMRC through compatible software. Check GOV.UK's guidance on using Making Tax Digital for Income Tax for the current rules and start dates. If you are unsure whether the rules apply to you yet, read our guide to MTD for Income Tax eligibility.

What counts as a digital link

MTD does not only require that you submit through software. It also expects your records to move between programs in a digital way. If your figures start in a banking app, move into a spreadsheet, and then into bridging software, the transfers between those steps need to be digital and not retyped by hand.

Whether a particular method counts depends on HMRC's current rules, so check the guidance rather than assuming. As a practical principle, avoid any step where you read a number off a screen and type it somewhere else. That is where mistakes creep in and where digital link rules can be broken.

Bridging versus full accounting software

How to choose a product

Start with HMRC's list of software that works with Making Tax Digital. Read it on GOV.UK's software finder, where you can filter by features such as bridging. Then check a few practical points:

• Does it support the type of income you have, for example self-employment or property?
• Does it work with the spreadsheet format you already use?
• What does it cost, and does the price change as your business grows?
• Can it handle the quarterly updates and the end-of-year steps, not only one of them?
• Does the provider offer support if a submission fails?

Prices and features change, so check the current position with each provider rather than relying on an old comparison.

Setting up before your first update

The first quarterly update is not the moment to discover a problem. Give yourself time to do a few things in advance. Sign up for your Government Gateway details if you do not have them, authorise the software to talk to HMRC, and set up your spreadsheet in the layout the bridging tool expects. Many tools need clear columns for dates, descriptions, income and expense categories.

Then run a practice period. Enter a few weeks of real transactions and check that the totals in the bridging tool match your spreadsheet. If you have questions about timing, see our guide to MTD quarterly update deadlines.

Worked example (illustrative)

"Tariq", an illustrative example, drives for a private hire operator and keeps a simple spreadsheet. Each week he adds his earnings from the platform statement and a handful of costs such as fuel and phone use. He has around twenty rows of data a month, so a spreadsheet works well for him. He picks a bridging tool from HMRC's list, links it to his Government Gateway account and tests it on a trial period.

Compare "Maya", another illustrative example, who has a small shop with hundreds of card payments and supplier invoices each month. She finds that keeping her spreadsheet up to date takes hours. For her, accounting software with a bank feed could cut the time spent and reduce errors. The choice is less about which tool is cleverer and more about how many transactions you have and how you like to work.

Keeping your spreadsheet bridging-friendly

A spreadsheet that works for you may not work for a bridging tool. Most tools read data from a defined layout, so a few habits help. Keep one row per transaction, with a clear date, a short description, an amount and a category. Avoid merged cells, blank rows in the middle of your data and notes typed into number columns. Use a separate tab for each tax year or period so that totals are easy to find and do not get mixed up.

Use consistent categories that match the categories HMRC expects in an update, such as turnover and the main expense headings. If you rename categories half way through the year, your totals can drift. It is worth agreeing the category list at the start and keeping to it. Save a backup copy after each submission, so you can show what was sent and when.

Who is bridging least suited to?

Bridging works well when the spreadsheet is small and tidy. It is a poorer fit when several people edit the file, when you receive hundreds of transactions a month, or when you need invoices, VAT or payroll alongside your income tax records. In those cases the time you spend maintaining the spreadsheet can outweigh the cost of proper software. Another warning sign is a spreadsheet that only one person understands. If it breaks, or that person is unavailable at a deadline, there is no fallback.

A sensible test is to ask how long your bookkeeping takes each week and how often you find mistakes when you reconcile to your bank. If the answers are "too long" and "often", it is time to look at software that imports bank data for you.

Common mistakes

• Assuming any spreadsheet tool works. Only software that connects to HMRC and is listed as compatible can submit your figures.
• Retyping figures between programs. This can break the digital link rules and introduces errors.
• Leaving set-up until the deadline. Authorisation and testing take time. Do them early.
• Forgetting the year-end steps. Quarterly updates are only part of the process. Check what is needed at the end of the year as well.
• Not keeping the underlying records. Keep receipts, invoices and platform statements that support the figures in your spreadsheet.

If you are weighing up a spreadsheet against proper software, our MTD compliance team can help you set up a workable system, and our bookkeeping service can take the record keeping off your hands. Get in touch through our contact page if you would like a conversation.