The official Government Help to Buy website
A mortgage supported by the Help to Buy: mortgage guarantee scheme works in exactly the same way as any other mortgage except that under the scheme the Government offers lenders the option to purchase a guarantee on mortgage loans.
Because of this support, lenders taking part are able to offer home buyers more high loan-to-value mortgages (80-95%).
You will still be fully responsible for your mortgage repayments. So if you have a 5% deposit, you will need to take out and pay back a 95% mortgage.
Example: for a home with a £200,000 price tag