T-Mobile charges $25 to $50 per month to add a line, depending on your plan and whether you bring your own phone
The cost of adding a line to T-Mobile depends on which plan you have and whether you're adding a phone or just a SIM card. On T-Mobile's main plans, a new line typically costs $25 to $50 per month. If you bring your own phone, you pay the lower end. If T-Mobile provides the phone, you also pay a device payment that runs separately from your monthly line charge.
T-Mobile's pricing structure changed in recent years, and the company now bundles some services differently than it did before. The actual cost you see depends on whether you're on a Magenta, Magenta MAX, or older plan, and whether you're adding a phone to an existing account or starting fresh.
Key Takeaways
- Adding a line to an existing T-Mobile account costs $25 to $50 per month depending on your plan type and whether you bring a phone.
- Phones purchased through T-Mobile add a separate monthly device payment on top of the line charge, usually $15 to $40 per month depending on the phone.
- Bringing your own phone to T-Mobile costs less per month than having T-Mobile provide one, but you pay the full phone price upfront.
- T-Mobile sometimes offers promotions that waive or reduce the line charge for a limited time, particularly for new customers or during sales events.
Monthly line charges on T-Mobile's current plans
T-Mobile's two main consumer plans are Magenta and Magenta MAX. On Magenta, adding a line costs $25 per month. On Magenta MAX, adding a line costs $50 per month. These prices assume you already have at least one line on the account; the first line on a new account costs more.
If you have an older T-Mobile plan from before the Magenta rebrand—such as T-Mobile ONE or Simple Choice—your line addition cost may differ. T-Mobile has kept some older plans available, and their pricing varies. You can check your current plan name by logging into your T-Mobile account online or calling T-Mobile customer service at 611 from a T-Mobile phone.
These monthly charges cover the line itself: the phone number, the SIM card, and the data and calling service. They do not include the cost of a phone if T-Mobile provides one.
Phone costs when T-Mobile provides the device
If you want T-Mobile to provide a phone, you pay two separate charges: the monthly line charge ($25 or $50) plus a monthly device payment. Device payments typically range from $15 to $40 per month depending on the phone's retail price. A $400 phone might cost $17 per month over 24 months; a $1,000 phone might cost $42 per month.
T-Mobile offers phones at various price points, from budget models around $100 to flagship phones over $1,000. The device payment is separate from the line charge and appears as a distinct item on your bill. Once you finish paying for the phone, the device payment stops, but the monthly line charge continues.
T-Mobile sometimes offers trade-in credits that reduce or eliminate the device payment. If you trade in an older phone, T-Mobile may credit you $200 to $800 toward the new phone's cost, depending on the phone's condition and model. This credit reduces your monthly device payment.
Bringing your own phone to T-Mobile
If you already own a phone, you can bring it to T-Mobile and pay only the monthly line charge—$25 on Magenta or $50 on Magenta MAX—with no device payment. The phone must be compatible with T-Mobile's network. Most phones sold in the United States work on T-Mobile, but older phones or phones from certain carriers may not.
To check if your phone works, visit T-Mobile's compatibility checker on their website or ask in a T-Mobile store. You'll need your phone's model number or IMEI (a unique identifier found in your phone's settings). If your phone is compatible, you can activate it by purchasing a SIM card at a T-Mobile store or online, or by ordering a SIM card to be mailed to you.
Bringing your own phone is the cheapest ongoing option because you avoid the device payment entirely. However, you pay the full phone price upfront when you buy it, rather than spreading the cost across 24 months.
Temporary discounts and promotional pricing
T-Mobile regularly runs promotions that reduce or waive the line charge for new lines. These offers typically last three to six months and apply to new customers or customers adding their first line in a certain period. For example, T-Mobile might offer a free line for three months when you add a line to an existing account, or a $100 bill credit toward a new phone.
Promotional pricing changes frequently and varies by region. To see current offers, check T-Mobile's website, visit a T-Mobile store, or call 611 from a T-Mobile phone. Promotions often require you to activate the line within a specific timeframe and may have other conditions, such as keeping the line active for a minimum period.
If you're considering adding a line, it's worth asking about current promotions before you commit. A promotion can reduce your first-year cost significantly, even if the regular monthly charge remains the same afterward.
How adding a line affects your total bill
When you add a line, your total bill increases by at least the monthly line charge. If you're on Magenta with a $25 line charge and no phone, your bill goes up by $25 per month. If you add a phone with a $20 monthly device payment, your bill goes up by $45 per month.
Some T-Mobile plans include perks like Netflix, Apple Music, or international roaming that apply to all lines on the account. Adding a new line does not duplicate these costs; you pay for them once per account, not once per line. This can make the effective cost of a new line slightly lower if you were already paying for these services.
T-Mobile's bill also includes taxes and regulatory fees, which vary by location. These fees are calculated on your total bill, so adding a line increases them slightly. The exact amount depends on your state and city.
Comparing T-Mobile line costs to other carriers
Verizon and AT&T charge similar amounts to add a line: typically $25 to $50 per month depending on the plan. Smaller carriers like US Cellular, Boost Mobile, and Cricket Wireless often charge less per line, sometimes $15 to $35, but their plans may include fewer features or slower data speeds.
If you're deciding whether to add a line to your existing T-Mobile account or switch to another carrier, compare not just the line charge but also the total cost of the plan, the coverage in your area, and any perks included. A cheaper line charge on another carrier might not save money if the overall plan is more expensive or if coverage is worse where you live.
Frequently Asked Questions
Can I add a line to T-Mobile without a phone?
Yes. You can add a line with just a SIM card and pay only the monthly line charge ($25 or $50 depending on your plan). You can use any compatible phone you already own or buy one separately from another retailer.
What happens to my bill if I cancel a line?
The monthly line charge stops immediately. If you're still paying for a phone on that line, you may owe the remaining balance as a final charge, or T-Mobile may allow you to pay it off over time. Check your account or call T-Mobile to understand your specific situation.
Do I pay the line charge even if I don't use the line?
Yes. Once a line is active on your account, you pay the monthly charge whether or not you use it. If you want to stop paying, you must remove the line from your account.
Can I move a phone from one line to another without paying again?
Yes. You can move a phone between lines on the same account without additional charges. The device payment stays with the phone, not the line. If you move the phone to a different account, T-Mobile may require you to pay off the remaining balance first.
Does T-Mobile charge a setup fee to add a line?
T-Mobile does not typically charge a separate setup or activation fee to add a line to an existing account. If you add a line in a store, there is no additional fee. If you add a line online, there is no fee. Some older accounts or special circumstances may differ; check your account or ask T-Mobile directly.