← Back to New Mexico

Los Alamos County Property Tax Due Date

New Mexico

(505) 662-8070

2026 Property Tax Due Dates

Official Source
Installment 1

November 10

First half

Installment 2

April 10

Second half

Pay Taxes Online →
Penalty: $5 minimum + 1% monthly interestGrace period: Until Jan 10 / May 10

Payment Methods

Online, Mail, In-Person

Los Alamos County Treasurer

Office Address

PO Box 30
Los Alamos, NM 87544

Get Directions

Office Hours

Mon-Fri 8am - 5pm

How to Pay

Online

Pay using credit card or e-check

Visit Website →

By Mail

Mail check payable to Los Alamos County Treasurer

Visit Website →

In Person

Visit the Treasurer's office — PO Box 30, Los Alamos NM 87544, Mon-Fri 8am - 5pm

Visit Website →

About Los Alamos County

Los Alamos County (English: "The Poplars" or "Cottonwoods"; Spanish: Condado de Los Álamos) is a county in the U.S. state of New Mexico. As of the 2020 census, the population was 19,419. The smallest county by area in the state, Los Alamos County was formed from parts of Sandoval and Santa Fe counties on June 10, 1949.

Source: Wikipedia — content available under CC BY-SA 4.0

Get Deadline Reminders

We'll email you 14 days before your property taxes are due.

Due dates shown are for reference only. Contact your county treasurer's office to confirm official deadlines before making payments.