Each lender has a different policy. Some banks do not allow rate lock for 10 year or 15 year fixed rate loans.\rThis is because a small change in their cost of funds before the loan is advanced could make the loan completely unprofitable for them, even though they are charging a rate lock fee.\rWhereas for a 1 year, 2 year, 3 year, 4 year or 5 year fixed rate loan, rate lock is available from almost all lenders.