About Diagonalise

What Diagonalise is, and isn't

It does a few things for one-person businesses, and tries to do them well.

• It is invoicing, expenses and Self Assessment figures, organised by the 6 April tax year
• It's built for one-person businesses in the UK: sole traders, freelancers and contractors
• If you run your own limited company, it handles your invoicing, payments and expenses, with your company and VAT numbers on every invoice
• Its tax reports are for Self Assessment, so it won't do Corporation Tax or a company's year-end accounts
• It isn't full double-entry accounting software, and it doesn't do payroll

How your data is looked after

Your figures are your business. Here's what happens to them.

• Names, addresses and bank details are encrypted before they're stored
• Export your expenses and reports as CSV files whenever you like
• If you stop paying, you move to the Free plan and keep all your data
• We only set cookies the site needs to work: no analytics or advertising cookies
• We don't sell your data or use it for advertising

The details are in our privacy policy.