When you close on a mortgage, your lender typically sets up an escrow account to handle property taxes and homeowner's insurance on your behalf. At closing, those costs are estimated based on the information available at the time, which may not match what your local tax assessor or insurance carrier ultimately charges. Within the first year, your lender is required to perform an escrow analysis, comparing the estimated costs to the actual bills being paid. If the actual costs run higher than the estimates, your monthly payment gets adjusted upward to cover the difference and rebuild a small cushion in the account.

One of the biggest drivers of an escrow shortage is a property tax reassessment. In many states, the act of purchasing a home triggers a new tax valuation, which can push your annual tax bill well above what the previous owner was paying. Insurance is the other common culprit. Premiums can shift due to changes in the property's assessed value, local risk factors, or simply because the carrier your lender used at closing was different from the one servicing the policy going forward. Even small changes in either of these line items can add up to a noticeable bump in your monthly payment.

When your payment changes, your lender is required to send you a written explanation detailing the new escrow breakdown. That letter will show what was collected, what was actually paid out, and how the shortage or surplus was handled. If anything looks off, or if you want to better understand what is driving the change, that is a good moment to pick up the phone and talk it through with your loan officer. Going forward, planning for the next annual analysis is easier when you keep an eye on local tax assessments and review your insurance coverage each year.