If you've kept your own Excel or Google Sheets for years, you don't have to move to full accounting software. Bridging tools submit your numbers for you.
Bridging software is the cheapest, least disruptive MTD route: you keep your spreadsheet, the bridging tool reads the totals and submits them to HMRC. Prices start from free (My Tax Digital, VitalTax free tier) to £12–£36 per year.
3 providers match this situation. Free options first.
Free bridging from Excel / Google Sheets.
My Tax Digital offers a free bridging mode that imports figures directly from spreadsheets and submits to HMRC. Also has a free accounting mode for simple digital records.
Excel add-in bridging, free tier available.
VitalTax is an Excel add-in that submits directly from your spreadsheet. Free tier for very small traders, paid tiers very cheap.
Cheap bridging software for spreadsheet users.
123 Sheets is a low-cost bridging tool, keep your records in Excel, it handles the HMRC submission. No bells, no whistles, just cheap compliance.
Bridging software is the legal middleman between your spreadsheet and HMRC. MTD rules require that your records are digital *and* that the link from records to HMRC is also digital, no copy-paste, no re-typing into a portal. A bridging tool reads the cells you point it at (income, expenses, mileage, property income) and submits those totals to HMRC's MTD API. That's it. It doesn't restructure your bookkeeping, doesn't replace Excel, and doesn't take over the records themselves. You still own the spreadsheet.
Most bridging tools are built around Excel (.xlsx). 123 Sheets, My Tax Digital and Tax Optimiser all accept Excel files directly. VitalTax goes further, it runs as an add-in *inside* Excel, so the submission happens without leaving the workbook. Google Sheets isn't natively supported by most bridging tools, but it works fine: download the sheet as .xlsx and upload it. Numbers (Apple) and OpenOffice/LibreOffice users should export to .xlsx first.
Bridging is the cheapest MTD route by a wide margin. Free options: My Tax Digital (free forever) and VitalTax (free tier for very low volumes). Cheap paid options: 123 Sheets at £12–£36 per year, Tax Optimiser at around £30 per year. Compare that to £84/yr for Xero's Simple plan or £144+/yr for QuickBooks. If all you need is the MTD submission step, paying £15/yr instead of £84/yr is the obvious move, you're not getting any less compliance, just less software around it.
Bridging works when you already have a working spreadsheet habit. It doesn't work well if you don't. The tool gives you zero structure, no chart of accounts, no expense categories, no reconciliation against bank feeds, no reports. If you currently scribble receipts into a shoebox, bridging won't help you; pick a free accounting tool (QuickFile, Pandle, HMRC's own tool) instead. Bridging is also a poor fit if you're VAT-registered with complex partial-exemption rules, or if you want management accounts your accountant can work from.
For most people the choice is between four tools. VitalTax (free tier + Excel add-in) is the slickest for Excel-native workflows. My Tax Digital is free forever, simpler interface, runs in browser. 123 Sheets is the cheapest paid option (£12–£36/yr) and the best-known. Tax Optimiser is a strong alternative for landlords with multiple properties. All four are HMRC-recognised for MTD Income Tax and MTD VAT.
MTD bridging software is a tool that connects a spreadsheet (usually Excel) to HMRC's Making Tax Digital service. It reads totals from cells you specify and submits them to HMRC as your quarterly update or VAT return. You keep your records in the spreadsheet, the bridging tool just provides the legally-required digital link to HMRC.
My Tax Digital is free forever for both MTD Income Tax and MTD VAT. VitalTax has a free tier for very low transaction volumes. If you need a paid option, 123 Sheets is around £12–£36 per year, far cheaper than full accounting subscriptions.
Yes. MTD doesn't force you to switch to accounting software, it requires digital records and a digital submission link. Bridging software gives you that link without changing your spreadsheet workflow. HMRC explicitly accepts spreadsheets + bridging software as MTD-compliant.
Indirectly. Most bridging tools accept Excel (.xlsx) files, not Google Sheets directly. The fix is simple: export your Google Sheet as Excel and upload it to the bridging tool. Some users automate this with a scheduled Google Apps Script export.
Yes, for real. My Tax Digital is free forever with no transaction limits. VitalTax's free tier caps at very low volumes but is free for as long as you stay under. HMRC's own free tool is free for simple cases but isn't a bridging tool, it expects you to enter figures directly.
It works if your rental income tracking already lives in a spreadsheet and you don't need property-by-property profit and loss. 123 Sheets and Tax Optimiser both handle property income. If you want per-property breakdowns, expense categorisation, or rent tracking, a landlord-focused tool like Hammock or Landlord Studio is a better fit.
Accounting software (Xero, QuickBooks, FreeAgent) replaces your spreadsheet, you do your bookkeeping in the app and it handles MTD submission as one feature among many. Bridging software keeps your spreadsheet and only handles the submission step. Bridging is cheaper but gives you no bookkeeping, reporting, or bank feeds.