Should Pre-Approval Letter Contain Interest Rate?

[Nick Louie]

Hi BP Community,

I'm a first-time home buyer in New York City. I was wondering whether a pre-approval letter from a bank should always contain the pre-approved amount plus the interest rate for the duration of the term? 

My lender told me that I cannot lock a rate until you are in contract to purchase. Is this accurate? 

Thanks! 

Regards,

Nick