# Bought a home in LA County? Plan for the supplemental property tax bill

> Why a purchase in Los Angeles County can lead to one or two supplemental property tax bills, why escrow and lender impound accounts usually do not pay them, and what to do when the notice arrives.

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- Language: en-US
- Category: Property taxes
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- Reviewed: 2026-10-31
- Review by: 2027-04-29

Many Los Angeles County buyers are surprised by a property tax bill that arrives months after closing. It is usually a supplemental bill created by the change in ownership, and it is separate from the regular annual bill.

## Key takeaways

- A purchase is a change in ownership that triggers a reassessment and can produce supplemental tax bills.
- The county mails supplemental bills to the owner; they are not paid by escrow and are not included in lender impound accounts.
- A closing between January 1 and May 31 can produce two supplemental bills.

## What a supplemental bill is

When you buy a property, the Los Angeles County Assessor reassesses it as of the date ownership changed. If the new value is higher than the prior assessed value, the difference is billed on a supplemental tax bill, prorated for the months remaining in the fiscal year. If the new value is lower, the county explains that a refund may result instead.

## Who receives it and who pays it

The Los Angeles County Treasurer and Tax Collector explains that supplemental bills are sent only to the property owner, even when a lender maintains an impound account, and that supplemental taxes are not paid by the title or escrow company at closing. Plan to pay the bill yourself unless your lender confirms otherwise in writing.

- Keep your mailing address current with the county after closing.
- Set aside funds after closing for a possible supplemental bill.
- Read every county notice for its due dates and instructions.

## Timing: one bill or two

The county explains that a change in ownership between January 1 and May 31 generally results in two supplemental assessments: one for the rest of the fiscal year in which the purchase happened and one for the following fiscal year. Purchases at other times generally produce one supplemental assessment.

## Before the bill: the notice

The Assessor mails a Notice of Supplemental Assessment before the bill. Review the value shown. If you disagree, the notice and the Assessment Appeals Board explain how and by when to file an appeal; check the deadline printed on your notice rather than relying on a general rule. A qualified tax professional can help with property-specific questions.

## Primary sources

- [Los Angeles County Treasurer and Tax Collector: New property owner](https://ttc.lacounty.gov/new-property-owner/)
- [Los Angeles County Assessor: Real property and reassessment](https://assessor.lacounty.gov/homeowners/realproperty)

## Scope and verification

This guide is general educational information, not real estate, legal, tax, financial, lending, architectural, engineering, contracting, appraisal, or transaction-specific advice. Verify property, title, permit, disclosure, contract, value, neighborhood, license, and availability facts with the responsible original source or qualified professional.

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