NOTICES
October 15, 2026 – New pay-by-mail processing service
Marin Water implemented a new lockbox service to receive mailed-in payments at Marin Water Payment Center, P.O. Box 515348, Los Angeles, CA 90051-6648. Customers paying their bill by mail should mail their check payable to Marin Water to this new processing center.
Spring 2025 – Implementation of a new bill pay system for customers
The modernized online billing portal by Paymentus offers expanded payment options and intuitive features, improving account management and customer service. View FAQs below to learn more.
Ways to pay your bill
- Online Payments: Enroll in autopay or make a one-time payment through our secure online payment system using your credit card or checking account, Venmo, Apple, Google Pay. You’ll receive a username and password when you register for an online account with us. Payments post within three to five business days. Access online payment system.
- Pay-by-Phone: Make a one-time payment or enroll in autopay over the phone 24/7 at 866.332.2444.
- Mail Payments: Payments post on the following business day after receipt of payment. Mail a check payable to Marin Water in the reply envelope enclosed with your bill’s payment coupon to Marin Water Payment Center, P.O. Box 515348, Los Angeles, CA 90051-6648.
- Pay in Person: Visit Marin Water’s Customer Service office at 220 Nellen Ave., Corte Madera, CA 94925, during regular business hours (Monday-Thursday, 8 a.m. – 4:30 p.m.), excluding holidays. After hours payments may be made in the drop box in front of the building.
Frequently asked questions
Did Marin Water change the pay-by-mail address?
In October 2026, Marin Water implemented a new lockbox service which allows mailed-in payments to be processed directly by the District’s bank’s service center. As part of this change, a new address is listed on the customer bill payment coupon. Customers who wish to pay by mail should now mail their check payable to Marin Water to Marin Water Payment Center, P.O. Box 515348, Los Angeles, CA 90051-6648.
Will the new pay-by-mail location delay when my payment is posted?
No, payment will not be delayed as long as the payment coupon is included for each payment. Since the new lockbox service receives mail deliveries multiple times per day, payments will be posted the same or sooner as the previous location in Corte Madera, which received payments only once per day. Payments will post by the following business day after receipt.
With the change in pay-by-mail address, am I still able to pay in person at the public counter or at the drop box in front of Marin Water?
Yes, customers can still make payments in person at Marin Water’s Customer Service office at 220 Nellen Ave., Corte Madera, CA 94925 during regular business hours (Monday-Thursday, 8 a.m. – 4:30 p.m.), excluding holidays. After hours payments may be made in the drop box in front of the building.
If I sent my payment to the old pay-by-mail P.O. box address in Corte Madera, will it still be received?
Yes, payments sent to the previous pay-by-mail P.O. box address in Corte Madera will still be received and processed by District staff in this transition period.
What are the benefits of the online billing system for customers?
The online bill portal by Paymentus, implemented in spring of 2025, has a much more intuitive, modernized interface for customers, allowing for easier self-service account management. It also offers multiple payment options, a quick one-time payment feature, the option to sign up for paperless billing with email reminders and the opportunity to schedule automatic payments from your checking account or credit card. While customers can still reach Marin Water’s dedicated customer service team by phone or in person Monday through Thursday, 8a.m. to 4:30p.m., the new system offers pay-by-phone 7 days per week.
How can I make a payment online?
If this is your first time using Marin Water’s online payment system, register using your six-digit customer number found in the upper right corner of your bill. Customers can also make quick one-time payments without setting up an online account.
What should I do if I can’t remember my username or password?
If you know your username, select “Forgot your password” on the Paymentus customer portal login page. In some cases, your user ID may be your email address. If you forgot your username, or need additional support, representatives from Paymentus are available 24/7 at 800.420.1663.
If I am enrolled in EasyPay (direct debit), will I need to enroll in the new online bill system?
Marin Water will eventually sunset the EasyPay direct debit payment option at a later date (to be announced). Current EasyPay customers are encouraged to enroll in the online bill payment options available through the new system. Please contact Marin Water Customer Service to cancel EasyPay if you enroll in a new bill pay option.
Is the online billing site secure?
Online bill pay is one of the safest ways for customers to pay their bills. The regulations governing online payments are rigorous and consistently updated to meet new market challenges and requirements. The Paymentus platform is independently audited and fully compliant with the latest regulations such as Level 1 PCI, NACHA, PII, HIPPA and more.