It looks as though it's 16.5% if you spend less than 2% of your turnover on goods:
"In the Autumn Statement, Chancellor Philip Hammond announced changes which affect businesses which have a very low cost base. These businesses are now called "limited cost traders".
Limited cost traders can still use the Flat Rate Scheme, but their percentage will be 16.5%. So if they sell £120 of work, including £20 of VAT, the flat rate amount is £19.80 (£120 x 16.5%).
A limited cost trader is defined as one that spends less than 2% of its sales on goods (not services) in an accounting period.
When working out the amount spent on goods, it cannot include purchases of:
capital goods (such as new equipment used in a business)
food and drink (such as lunches for staff)
vehicles or parts for vehicles (unless running a vehicle hiring business)
A firm will also be a limited cost trader if it spends less than £1,000 a year, even if this is more than than 2% of the firm's turnover on goods."
I'm not sure for example if fuel is included in the 2%. To be honest if all goes to plan after next year we'll be over the flat rate eligibility anyway, but paying VAT every quarter is a burden.
