Bad credit or a low credit score are always likely to increase the interest rates you are quoted on a mortgage, or make it harder to find a lender that will approve your application.
There are different degrees of severity, so if you have minor credit issues such as a couple of late payments, it's likely to make much less of an impact than something more serious such as a bankruptcy or repossession.
Lenders will also consider how long ago the issues occurred, and rely on their lending policies to assess how much of a risk factor it presents.
Revolution Brokers works with a vast network of bad credit specialist lenders, so if you have been turned down for a Help to Buy mortgage or want to compare the best rates on the market, get in touch on 0330 304 3040.