Every lender quotes you on the same three-page federal form, the Loan Estimate, and the rules attach consequences to it: some figures on it cannot legally increase at closing, some can rise by up to ten percent in aggregate, and some are estimates with no ceiling. The form does not label which is which. The rules do.
The three buckets
Zero tolerance: the lender's own charges — origination fees, points, and the services they pick for you where you had no say — plus transfer taxes. These cannot increase at closing absent a legitimate changed circumstance, which the lender must document.
Ten percent in aggregate: recording fees, and third-party services where you chose a provider from the lender's own list. The bucket as a whole can rise ten percent; any single line inside it can move more.
No tolerance limit: prepaid interest, homeowner's insurance, escrow deposits, and services where you chose your own provider off-list. These are honest estimates of third-party facts, and they move.
Why this matters before closing, not at it
The buckets are enforced by comparing your final Closing Disclosure against your Loan Estimate — which means the enforcement only happens if somebody does the comparing, inside the three-day window the law creates for exactly that purpose. A fee that jumped in a zero-tolerance line is not a negotiation; it is a correction the lender owes you.
Between lenders, the zero-tolerance bucket is also the honest basis for comparison, because it is the part each lender actually controls. Two quotes that look far apart on their totals are frequently identical once the pass-through costs are stripped out — and sometimes the reverse.