The short answer
If you have Oklahoma Natural Gas service, ONG offers rebates of up to $1,100 on a new natural gas tankless water heater. You apply within 180 days of installation, using your paid installation invoice.
Which ONG rebate fits your home
- $1,100: replacing an electric water heater with a new natural gas tankless water heater (Uniform Energy Factor .80 or higher, purchased and installed after December 31, 2023)
- $250: a new natural gas tankless or condensing water heater (Uniform Energy Factor .80 or higher)
- $850: replacing an electric water heater with a new natural gas tank water heater
Amounts are from ONG's rebate page. Rebates are limited and paid first-come, first-served while program funds last.
How to apply in 4 steps
- Make sure you have an active Oklahoma Natural Gas account.
- Have a qualifying natural gas tankless water heater installed (Uniform Energy Factor .80 or higher), installed to code.
- Get your purchase receipt and a paid installation invoice.
- Submit ONG's rebate application online, by email or by mail within 180 days of installation. ONG says checks or utility credits arrive about six to eight weeks after approval.
What to keep after installation
- Your paid, itemized invoice with the make and model number
- The purchase receipt for the water heater
- Your Oklahoma Natural Gas account number
- The installation date, so you know your 180-day window
Common mistakes that cost homeowners the rebate
- Waiting past the 180-day deadline
- Choosing a unit below the .80 Uniform Energy Factor
- Sending an invoice that does not show it was paid
Going tankless with Acts of Service Plumbing
We install natural gas tankless water heaters across the Tulsa metro, and you get a paid, itemized invoice with the model number for your rebate application. See our tankless water heater service or read a real tankless job story.
Official rebate details and the application are on Oklahoma Natural Gas's water heater rebate page.
Page last updated October 2026.
Straight Answers
How much is the ONG tankless water heater rebate?
Oklahoma Natural Gas lists a $250 rebate for a new natural gas tankless or condensing water heater with a Uniform Energy Factor of .80 or higher, and a $1,100 rebate when you replace an electric water heater with a qualifying natural gas tankless unit. Check ONG's rebate page for current amounts, since rebates are limited and paid while program funds last.
How long do I have to apply for the ONG rebate?
ONG asks for your application within 180 days after the date of installation.
What do I need to send ONG?
The completed rebate application, the water heater purchase receipt and the installation invoice. You also need an active Oklahoma Natural Gas account.
Do you help with the rebate paperwork?
Yes. After your tankless installation we give you a paid, itemized invoice with the model number, which is what ONG asks you to send with your application.
