12.10.25
What Is Data Roaming? How to Avoid Roaming Costs
by Kathy Hinson
February 5, 2026
What Is a Data Plan?
You need data as part of your phone plan if you'd like internet access while away from Wi-Fi. Here's what to know about the data portion of a phone plan and how to shop.
Written by Kathy Hinson
A data plan is a monthly internet service provided by mobile carriers that lets your phone, tablet, or other device connect to the internet using a cellular network. It lets you access online services and use apps when you're not connected to Wi-Fi.
When shopping for a phone plan, the issue of data use comes up quickly. If you’re new to choosing a phone plan — maybe you’re getting off your parents’ plan — or it’s just been a while since you’ve shopped, here’s a guide to what you need a data plan for and how to manage data use.
What is data used for on a cell phone?
Phones aren't simply for calling anymore. It's likely that most of your phone use involves using apps, browsing websites, streaming entertainment, scrolling social media, or sending texts with images or video, including RCS messsages. All of those things require an internet connection — so you either need a data plan to use your carrier’s cellular network or you'll need to be on Wi-Fi.
What is data on a cell phone plan?
The data portion of a phone plan shows how much access you get to the internet via your carrier’s cellular network. This cellular data is also called mobile data, because it lets you connect to the internet anywhere instead of being tied down to a physical location with a Wi-Fi network.
Phone plans measure data allowances in gigabytes (GB) or sometimes megabytes (MB), and plans can be limited or unlimited.
- With a limited data plan, you’re paying for a set amount of mobile data per billing cycle. If you run out, you have to buy more or wait for the next billing cycle to begin.
- With unlimited data plans, there’s no set cap on how overall data use. However, unlimited data plans often have some limits: Carriers may slow or “throttle” your data speeds after a certain level of use. You can still use data because it doesn't cut off — the speeds just won’t be as fast until the next billing cycle begins. Look for details about speeds and throttling policies under the broadband fact sheets on a carrier’s website.
There are also other types of data plans, such as tablet data plans and plans for wearables like smart watches. Sometimes you can get a tablet or watch data plan for free or at a discount when you pair it with an unlimited data phone plan.
What is shared data on a cell phone plan?
Shared data can come into play if you’re part of a family phone plan. Those plans can either grant each line its own data amount (most common) or can give an overall data amount pooled between all lines on the plan.
Can I have a phone without a data plan?
You can find some no-data plans, also called talk & text only plans, which don’t give any mobile internet access or offer very limited access (think 1GB or so). Those tend to be cheaper, but they tie you down to Wi-Fi for things like using apps, accessing email, streaming and so on. When you’re away from Wi-Fi, you’ll only be able to make calls and send messages through your default messaging app.
How do I know which data plan to choose?
Before shopping, estimate how much data you need for your typical activities so you know which plans to consider. It also pays to know about the different types of networks: 5G, 4LTE and 3G as well as the newest, 5G UC. The type of network you’re on affects how fast your mobile data performs, and it depends on your phone’s capabilities as well as your carrier and the plans it offers.
Also think about whether you want to use your phone as a hotspot that shares its data with other devices. If so, check whether plans you're considering include hotspot data and whether it comes from your overall data limit or is a separate data allowance.
>> Read More: How to select a cell phone plan
What uses cell phone data?
Once you’ve picked out a data plan, you’ll want to keep an eye on your mobile data use to make sure you’re not paying for more than you need or getting charged for using too much.
Anything that relies on an internet connection will use your mobile data if you’re not on Wi-Fi: browsing the internet, streaming media, scrolling social media, playing games, using maps, checking and sending email, making video calls.
