How lenders size a HELOC
Line limit = home value × maximum combined LTV − existing mortgage. Rates are usually prime + a margin and change with the prime rate.
FAQ
How much can I borrow against a $450,000 home?
With a $250,000 mortgage and an 85% CLTV limit, up to $132,500.
Sources (checked Nov 6, 2026): IRS Publication 936; CFPB HELOC guide.