Owning your modem with Optimum can save you a ton of money in the long term since they charge anywhere from $4.95/month to $9.95/month, just to use their leased modem. For most Optimum modem models, you could buy one and it will have paid for itself within less than 3 years. We feel that by that logic, there’s really no reason you should still be renting a modem.
Some people have mentioned to our support representatives that they don’t feel comfortable setting up their modem on their own as they don’t consider themselves to be very technically savvy. Luckily, in recent years companies have made doing a self-installation for your new cable modem much easier. This allows you to do the activation from home, and in most cases without calling out a technician to help you. We know that starting up new service or pulling the plug on renting your modem and trading it for a non-rental version can be a plunge, so we wanted to make sure you have all the information you need to get started!
How to Activate Your Modem with Optimum Cable
Activating your modem with Optimum is super quick and easy. You’ll need to set aside around 30 minutes for most activations to ensure you’re not feeling rushed.
- Plug in your modem to the power supply cable, then plug the power supply cable into the wall.
- Plug the coaxial cable into the wall, and then screw the other end into the coaxial port on the back of the modem.
- Wait 5 minutes for your modem to fully boot up. If your modem has built-in wireless, you’ll know your device is fully powered on once the wireless lights come on.
- Connect an ethernet cable into the back of your modem and then plug in the other end into your computer.
- Open a web browser (such as Chrome, Firefox or Safari) and type install.optimum.com into the URL web address bar at the top of the screen, then hit enter.
- To activate your modem you’ll need your 13-digit account number to register online, which you can find on your Optimum bill, a receipt from the Optimum store as well as several other places.
- Follow the on-screen steps to set up and activate your new modem.
- After set up is complete, you can now disconnect the ethernet cable from your computer or laptop and connect it into a wireless router if you’re using one for your wireless service.
Congratulations on activating your cable modem with Optimum service!
How to Reset Your Optimum Modem
Resetting your Optimum modem is an important skill to know since it’s used in so many situations. If you are doing any troubleshooting with your provider, forgot your WiFi password (if WiFi enabled) or you’re just trying to clear up an issue with your network, knowing how to reset your Optimum modem is an ideal first step. Here’s our easy guide on how to do it in less than 10 minutes:
- Plug in your modem to the power supply, then plug the power supply into the wall outlet.
- locate the reset button on the back of your modem where all the ports are.
- Press and hold down the reset button for 30 seconds with a paperclip or toothpick.
- After 30 seconds, release the reset button, then wait 5 minutes for your modem to power cycle and reset.

How to Log Into Your Optimum Modem
Logging into your Optimum cable modem allows you to adjust the settings, control WiFi credentials (if your modem is wireless-enabled) and much more. Knowing how to do this is important for some troubleshooting steps, enabling bridge mode, and changing your WiFi password (if applicable) among other important features.
For most users, this is something that you really only mess with occasionally, but is still important to know how to do. Here’s our quick, easy guide on logging into your Optimum modem:
- Connect your modem to the power supply and then plug the power supply into the outlet. Allow 5 minutes for your modem to fully boot up.
- Connect one end of an Ethernet cable into the back of your Optimum modem, and the other end into your computer.
- If your modem has built-in WiFi, you can connect to the wireless network instead, if that’s easier. Most Optimum modems do not have WiFi built-in though, and Ethernet is much more reliable.
- Open a web browser such as Chrome, Firefox, or Safari (not Microsoft Edge or Internet Explorer).
- Type the modem’s IP address into the URL / Address bar at the top of your browser window.
- Most Optimum compatible modems use 192.168.0.1 or 192.168.100.1 as their IP address, but if not it will be listed somewhere on the sticker on the bottom of your modem.
- Once you’ve typed in the IP address, press enter and it should load a page with either the manufacturer logo of the company that makes your modem, OR it will have an Optimum logo. At this point, most models will request a username and password to enter the settings panel. Most of the time, the credentials are as shown below, but sometimes they are listed on the modem’s sticker near the IP address.
- username: admin
- password: password
- Enter your login credentials then click submit.
How to Cancel Optimum Cable Internet Service
You can either call the customer service line or go online and find the account management section of the website to cancel your Optimum cable internet service. You might be asked for the reason for the cancellation as well as any other details required to complete the cancellation. Additionally, based on the conditions of your service agreement, you might be required to pay an early termination fee. Before terminating your service, it’s a good idea to review your agreement’s terms and any potential fees.
Did we answer all your questions about the How to Self-Install & Setup a Modem with Optimum Cable? Let us know in the comments, or leave your own questions for our technicians to answer!
Where do I find the Network security Key on my ARRIS Model TM1602A?
Hi Marietta,
This model does not have built-in WiFi, so there is no network security key for this device. If you’re using a wireless router alongside it, you can use the network security key or pre-shared key printed on that device. Otherwise, you’ll need to connect with the ethernet cable.
Hope that helps!
ModemGuides Support