Photo of people using a remote control to watch free TV using an antenna.

With more of us looking to find ways to save money on our monthly TV bills, it's no surprise that TV antennas have made a comeback.

Once you get an antenna, you can tune in to local broadcasts channels, such as ABC, CBS, Fox, and NBC, as well as PBS and Telemundo. It's free TV.

However, if you use an antenna, it's important to regularly rescan for channels. That's always been a good idea, but it's more important now—because many stations either have changed or will be changing the frequencies of their broadcasts over the next two years. (The transition started in April 2017 and won't be completed until July 2020.)

Rescanning simply means having your TV's tuner do an automated update to look for new channels. This will allow your TV to find your favorite channels at their new frequencies. Though the frequency may be new, the channel numbers you use won't change—channel 5 will still be channel 5, and so on.

More on TV Antennas

Why are stations moving? Several years ago, Congress authorized the Federal Communications Commission to hold a spectrum auction, freeing up some over-the-air broadcast TV frequencies to make room for new high-speed wireless services.

Now that the auction is complete, about 1,000 TV stations have to change their frequencies. In addition, about a dozen stations will go off the air entirely. And some new stations may come on line.

Numerous online resources can help you learn whether any local stations will be moving, and if so, when. For example, the National Association of Broadcasters has created a helpful website, TVAnswers.org. We also like the FCC's interactive DTV map on the agency's website. Both can provide general information about station reassignments, and you can find out when your local TV stations are moving just by entering your address or ZIP code. The TVAnswers site also lets you sign up to get alerts when a local station is moving.

The spectrum reassignment isn't the only reason to rescan every month or so.

If you did your original channel scan during a cloudy or rainy day, you might not be receiving all the channels available to you.

Second, most stations have been adding subchannels, in addition to the main program you're tuned to. A rescan will help you capture any of those new subchannels, with programming that often includes a mix of vintage TV shows, nature programs, weather, and foreign-language programming.

Here's How to Rescan

Fortunately, it's fairly simple to rescan for channels. The process varies a bit depending on what brand of TV you own, but ultimately you're looking for a control that says Channel Scan or Channel Tuning.

Start by using your TV remote control (or a digital converter box remote if you still have an older analog TV) to press the Menu or Setup button. You may see the Channel Scan control right away, or it could be one layer down, under Antenna, Channels, or Channel List. It might be called "Live TV" (for LG TVs) or "Broadcast" (for Samsung sets).

If you don't see any of those options as soon as you press the Menu button—and that's not unusual—you'll have to go one layer deeper by first choosing Settings or Setup.

Once you find Channel Scan or Channel Tuning, you may have a choice to tune automatically (Autotune or Autoscan) or manually. You want the automatic option, which will make the TV search through all the channels.  

If you don't see any of these options, you can usually perform a channel scan by selecting the Input button on the TV remote or in the TV's main menu, then choosing Antenna.

Depending on the number of channels you can receive, it could take a few minutes to complete the rescan. If it doesn’t work the first time, try again. We recommend doing a second channel scan anyway just to see whether you get any stations you missed on the first rescan.

If you're already using an antenna to get free TV, you'll probably only need to rescan your TV—you won't need any new equipment.

The one exception is if a local station moves from UHF (channels 14-51) to VHF (channels 1-13) and your current antenna is either UHF-only or gets poor VHF reception. In those cases, you might want to consider a new antenna. (More on that below.)

Don't Have an Antenna Yet?

If you're just getting started with free over-the-air TV, you're in good company. Even many consumers who have switched to streaming video services, such as DirecTV Now or Sling TV, use an antenna for local stations not included with their package. In fact, 20 percent of all U.S. households with internet service now use a TV antenna to get free TV service, according to Parks Associates, a market research firm.

Having the right antenna can help you get more of your local channels. In 2018, we tested 10 popular models, ranging in price from $10 to $80. Your reception will also depend heavily on your distance from broadcast towers, along with topography—such as mountains or tall buildings—that could interfere with signals. Amplified models can often help pull in more distant stations.

One final reminder if you are shopping for an antenna: Make sure it can receive both VHF and UHF frequencies. Some antennas provide good reception for only VHF or UHF channels, but not both. But you'll need an antenna that can receive both to get all the stations you can receive in your area.