The mortgage number moved, and the credit line moved faster
The Fed moved a quarter point, prime moved the next morning, and daily lender quotes were already above 7% before either.
The Federal Reserve's rate-setting committee raised its benchmark a quarter point on 16 September, to a target range of 3.75% to 4.00%. First increase since 2023, and the vote was 12-0. Chair Kevin Warsh, in remarks reported by Fox Business, said inflation "is too high and has been for too long."
The next morning, major banks repriced prime to 7.00%, reported by the Honolulu Star-Advertiser and tracked by fedprimerate.com. That same day, 17 September, Freddie Mac published its weekly survey at 6.95%.
The number
6.95% is the survey average on a 30-year fixed mortgage for the week ending 17 September. It was 6.76% the week before and 6.26% in the same week of 2025. Nineteen basis points in seven days, sixty-nine in a year. The 15-year came in at 6.26%, exactly where the 30-year sat last September.
Daily trackers read higher and got there earlier. Mortgage News Daily's 30-year index was 7.22% on 15 September, the day before the Fed met, 7.24% on the day itself, and 7.17% on 22 September, when Fortune's tracker showed 7.068%. So it crossed 7% before the meeting, eased after it, and stayed above 7%.
Freddie Mac averages lender quotes over roughly a Thursday-to-Wednesday window, weighted toward the cleanest borrower profiles, so it lags. One is a photograph of the week, the other of yesterday, and in a climbing week the photograph of the week is the flattering one.
Who pays whom
The Fed does not set fixed mortgage rates; it sets the overnight rate banks charge each other. A 30-year mortgage is priced off the 10-year Treasury yield, 4.98% on 18 September. The lender who writes the loan does not keep it.
It is sold on and ends up inside a mortgage bond, held by an investor who could buy a Treasury instead. If the Treasury pays 4.98%, the mortgage bond has to pay enough more to be worth the extra risk, and the borrower funds the difference.
The Fed's decision reaches that investor as a signal about inflation over ten years, which is why the daily quote was above 7% before the announcement and has not been back under since.
Prime is the exception. Banks set it at a fixed spread over the Fed's rate, so it moved the next morning. Anything priced off prime follows within days, not months: a revolving business line, a home equity line drawn for inventory, a card balance. No application, no signature. The payment rises at the next billing cycle. Nobody sends a letter when a credit line reprices.
A borrower already holding a fixed mortgage pays nothing extra. The rate is locked for the term. That is the whole feature of a fixed rate, and for anyone waiting to refinance, the whole problem. The Mortgage Bankers Association's seasonally adjusted refinance index for the week ending 11 September, which closed before the Fed met, ran 65% below the same week of 2025.
What it costs on a real loan
None of the reports reviewed for this piece ran the payment math. On a $500,000 30-year loan, principal and interest at 6.95% is $3,309.74 a month. At the prior week's 6.76% it was $3,246.31. One week added $63.43. Against 6.26% a year ago, the gap is $227.90 a month. Held to term, total interest is $691,506 at 6.95% against $609,462 at 6.26%, a difference of $82,044 for sixty-nine basis points.
Who it hits here
Bigger loans multiply the same move. On a $600,000 loan, going from 6.26% last September to 6.95% this week costs $273 more a month, $3,281 a year. On $750,000 it is $342 a month, $4,102 a year.
On $200,000 it is about $91. Those are illustrations, not survey data. A Lakewood or Monsey buyer financing a large house absorbs the move several times over; a Cleveland buyer on a smaller ticket absorbs it once.
The faster hit is the business owner's, not the homebuyer's. The mortgage number is still a quote. The credit line is already a bill.
What to watch
The 10-year Treasury was 4.98% on 18 September, two basis points under 5%. Fixed mortgage pricing follows that yield, not the Fed's rate.
The committee meets again 27 and 28 October. September's projections show the median committee member expecting one more quarter-point increase before year-end. If it lands, prime goes to 7.25% the following morning and every prime-linked line reprices inside a billing cycle.
Figures as reported by Freddie Mac, Mortgage News Daily, Fortune, NerdWallet, Fox Business, The Mortgage Reports, Mortgage Bankers Association and The Washington Post.
