Your payment jumped but your rate is fixed. It's the escrow — and it's workable.

Why did my payment jump if my rate is fixed?

Because a fixed rate only fixes part of the bill. A typical mortgage payment is really two payments: principal and interest — genuinely locked — and escrow, the account your servicer uses to collect and pay your property taxes and homeowners insurance. When the premium rises — and in Arizona it has risen hard these past few years — the escrow account quietly falls behind. Once a year the servicer re-runs the numbers, finds the account short, and bills you for two things at once: the shortage it already ran up, plus bigger monthly deposits for the year ahead. That's how a $600-a-year premium increase can land as $100 or more a month — roughly double the raw increase, because you're repaying yesterday's gap while prefunding tomorrow's cost. Nothing is broken — and it can be worked from both ends.

What exactly is an escrow analysis?

The once-a-year audit. Federal mortgage servicing rules (RESPA and its Regulation X) generally require your servicer to analyze the escrow account annually and send a statement showing what came in, what got paid, and the new monthly payment. Two details worth knowing. Servicers are generally allowed to hold a cushion of up to two months' worth of escrow payments — one-sixth of the year's expected bills — so part of the increase may be the cushion being rebuilt, not the premium itself. And because the analysis runs only once a year, an insurance increase from last August can ambush you the following spring. The statement has line items; read them before assuming anything.

Do I have to pay the shortage all at once?

Generally, no — the rules lean your way here. Under Regulation X, if the shortage is one month's escrow payment or larger, the servicer generally can't demand a lump sum: it can absorb the shortage or require repayment in equal installments over at least twelve months. (Shortages smaller than a month's payment can be called due within 30 days, though many servicers spread those too.) Most statements offer both numbers: lump now and a smaller monthly rise, or spread and keep your cash. The honest math: many servicers charge no interest on a spread-out shortage — check your statement — so the lump sum mostly buys a smaller monthly number, not a discount.

How do I actually get the payment back down?

Attack the cause. The tax half of escrow is hard to move; the insurance half is shoppable, and re-quoting typically costs nothing and creates no claim record. The sequence:

1. Re-shop the policy. An independent agent can compare several markets in one conversation — the useful move when the problem is one company's number.
2. Switch with zero gap. New policy starts the day the old one ends, with the servicer's mortgagee clause on it from day one. A gap — even a short one — is what triggers the scary lender letters.
3. Route the refund. Cancel the old policy mid-term and the unearned premium typically comes back to you or to escrow. Either way, it helps fill the shortage.
4. Ask for a new analysis, in writing. Servicers generally aren't required to re-run the analysis early, but many will on request once the cheaper policy is on file — which lowers the payment now instead of at next year's statement. And if an analysis shows a surplus of $50 or more, federal rules generally require it refunded within 30 days as long as you're current on the loan.

What if it's the taxes, not the insurance?

Sometimes it is — the analysis statement says so, line by line. Arizona property taxes are billed in two halves, due October 1 and March 1, so a valuation increase flows into escrow on the same annual cycle insurance does. If taxes drove the jump, the remedies are different: valuation appeals run through the county on their own calendar and deadlines (general information, not legal advice — the county's process governs). Still: even when taxes are the culprit, the insurance line is the lever you can pull this month, and a cheaper, equally solid policy offsets a tax increase inside the same escrow account.

The letter says "lender-placed insurance" — is that the same thing?

No — and it outranks everything above. That letter means the servicer believes you have no coverage at all and is about to buy an expensive policy on your behalf and bill your escrow, which makes this whole problem worse. Often it's just proof-of-insurance paperwork that never reached them, and the fix is fast. Here's the playbook for stopping it, removing it, and getting refunds — handle that first, then come back to the escrow math.