Spreadsheets and bridging software for MTD
You can keep your records in a spreadsheet under MTD for Income Tax, but you also need bridging software to send the figures to HMRC. 80 products on HMRC's list are bridging software.
Not tax advice. This site explains GOV.UK guidance in plain English. Your own position depends on your tax returns and circumstances. Check GOV.UK or ask an accountant before you act.
Spreadsheets are allowed
GOV.UK says if you use spreadsheets you can continue to use them, but you need software that links to them (bridging software) to send quarterly updates and submit your tax return (GOV.UK). Some bridging products can do both, so check before you choose.
Digital links: the rule to follow
Once a record is created and sent in an update, you must not move it by hand. That means no retyping figures into another cell or product, and no copy and paste. Allowed digital links include linked cells and formulas, importing or exporting files (CSV, XML), emailing a spreadsheet so it can be imported, or passing data on a memory stick for someone to import (GOV.UK).
If you correct a record, correct it in your spreadsheet and let the link carry it to the bridging software.
Using more than one product
You can use more than one product, for example one for records and quarterly updates and another for your tax return, or a different product for each business. But you can only use one product for each separate submission: a landlord cannot use two products for their property updates (GOV.UK).
How long to keep records
Keep your digital records for at least 5 years after the 31 January submission deadline for the tax year, the same as Self Assessment. This still applies if you change software.
Questions
Is a spreadsheet MTD-compatible software?
No. A spreadsheet on its own cannot send anything to HMRC. You need HMRC-recognised bridging software linked to it.
Is Google Sheets OK?
It depends on the bridging product. Check the provider's website for which spreadsheet apps it connects to.