Figure out who actually owns the account

Before you call anyone, log in to your carrier's app or website and check the account details. One of you is the primary account holder and one of you is a secondary line. This distinction matters enormously.

If you are the primary account holder, you have almost complete control. You can remove lines, transfer lines, or close the account entirely without your ex's permission. The carrier will ask for your account PIN or the last four digits of your Social Security number, but that is about it.

If your ex is the primary account holder, your options narrow. You can request to have your own line separated out and ported to a new individual account, which you have the right to do regardless of who owns the main account. What you cannot do is make changes to their account or remove them from it.

Write down: whose name is first on the bill, the account number, and the PIN if you know it. If you do not know the PIN and you are the primary holder, carriers will verify your identity through your billing address or the last four of your SSN instead. Do not skip this step and assume you will figure it out on the call. Carriers will put you back in the queue if you are missing basic credentials.

Decide whether to separate the lines or close the account

You have two main options, and the right one depends on your situation.

Option one: line separation. Your ex's number gets transferred off your account and onto their own new individual account. Their number, their contacts, their apps stay intact. You keep your number and your account continues with one fewer line. This is the cleanest outcome for both people if the goal is simply to stop sharing. Most major carriers (Verizon, AT&T, T-Mobile) allow this online, in-store, or by phone. Some require your ex to set up a new account in the same call; others let you initiate the split unilaterally and the ex receives instructions to complete their side.

Option two: account closure and starting fresh. If you are a secondary line and you want nothing to do with the existing account, you can port your number out to a new carrier entirely. You will need your account number and your account transfer PIN, sometimes called a number transfer PIN or port-out PIN. You can request this PIN from the current carrier before you leave.

A few things that trip people up: if your phones are still under installment plans, the remaining balance is due either at separation or it transfers with the line depending on the carrier's policy. Ask specifically. Also check whether you are still in a contract period. Early termination fees still apply, though most carriers have moved to installment-based models that just require paying off the device.

Handle the device installment plans and any shared balances

This is where things get sticky, and where people lose money by not asking the right questions before they hang up.

If either phone is being paid off in monthly installments, that installment plan is attached to the line or the account, depending on the carrier. When a line separates, some carriers require the balance to be paid in full before the line can move. Others transfer the installment obligation to the new account. Ask your carrier representative directly: what happens to the device balance when this line separates?

If your ex's device has a remaining balance and the installment is currently on your account, do not agree to carry it forward unless you have a written agreement with your ex about reimbursement. That installment balance is a real debt, and it sits on your credit history until it is paid.

Similarly, check your current bill for any outstanding balance before the separation. Carriers will not always flag this proactively. A $200 past-due amount left on the account is still yours to deal with if your name is on it.

If you have intertwined debts from the relationship more broadly, our piece on building a debt repayment plan after divorce walks through how to triage multiple obligations when everything is arriving at once.

Remove account access and update your security credentials

Separating the lines is step one. Locking down what remains of your account is step two, and people consistently skip it.

Change your account PIN and your online account password immediately after the separation is processed. If your ex knew your login credentials, they could still access account details, call records, or even add a new line if you have not changed the PIN. Most carriers also offer a secondary security question; change that too.

Check whether your ex is still listed as an authorized contact on the account. Authorized contacts can make changes, request information, and in some cases add features or lines without being the primary holder. Remove that authorization while you are on the call or in the app.

If you used a shared email address or family plan app for account management, switch to a personal email only you can access. Then do the same sweep on any other shared digital accounts: streaming services, cloud storage, password managers. This is also a reasonable moment to unfollow or mute your ex on social media if you have not already. Research consistently shows that people who do that, rather than continuing to monitor, process the breakup faster. It is not the sentimental part of this checklist, but it belongs here.

Confirm everything in writing and monitor your first solo bill

Before you end any call with the carrier, ask the representative to send a confirmation email summarizing what was changed. Get the representative's name and a case or ticket number. Carrier systems can be slow to update and verbal assurances sometimes do not make it into the account notes.

Set a reminder to check your next bill closely. Confirm that your ex's line no longer appears, that the installment plan situation matches what you were told, and that no new charges appeared around the time of the change. Errors happen, and catching them on the first bill is much easier than disputing three months of incorrect charges later.

If you added a new line or changed your plan tier during the process, verify that the rate matches what was quoted. Promotional pricing sometimes requires a specific plan configuration, and separating a line can inadvertently change your eligibility.

Finally, if your ex is uncooperative and you are the primary holder but they have physical possession of a device that is still on an installment plan attached to your account, consult your carrier about a lost or stolen device report and speak with a family law attorney about your options. Do not make that move without understanding the legal implications first.