You mean offering a 4% rate on a new home right? Otherwise it's only a win for the bank! It's complicated with mortgages because, in the US, mortgages are most

You mean offering a 4% rate on a new home right? Otherwise it's only a win for the bank! It's complicated with mortgages because, in the US, mortgages are mostly securitized and resold. This covers 65% of mortgages in 2022 according to https://www.newyorkfed.org/medialibrary/media/research/staff_reports/sr1001.pdf https://www.newyorkfed.org/medialibrary/media/research/staff... So your mortgage isn't directly on your bank's book. The bank sold it, and then likely bought it back but as part of an MBS. In the US, there are a lot of small banks that rely on this to reduce their exposure to property prices in the local area they originate mortgages in.