Postpaid Phone Churn: Measuring Wireless Customer Retention

Postpaid phone churn measures the rate at which postpaid phone customers or connections terminate service during a period.

A simplified monthly formulation is:

1Postpaid Phone Churn
2≈ Postpaid Phone Disconnects
3÷ Average Postpaid Phone Customer Base

The exact numerator, denominator, restoration rules, and monthly averaging method are issuer-defined.

Churn is a rate, not a subscriber count

Postpaid Phone Net Additions measure the net balance of additions and losses. Churn measures the loss rate relative to the installed customer base.

A large carrier can post more absolute disconnects than a smaller carrier while still reporting a lower churn rate because the denominator is larger. Conversely, low churn does not guarantee strong net additions if gross additions are weak.

Definitions differ across carriers

T-Mobile defines churn as deactivated customers divided by the average number of customers during the period and then divided by the number of months in the period. It also nets out customers whose service is restored within a specified time and excludes customers who received service for less than a minimum period.

Verizon defines wireless churn as the rate at which service to retail, postpaid, or postpaid phone connections is terminated on average in the period, using disconnects divided by the corresponding average connection base.

AT&T separately reports total postpaid churn and postpaid phone churn, which illustrates why the population label matters.

Phone churn and total postpaid churn are not interchangeable

Total postpaid populations can include:

• phones;
• tablets;
• watches and wearables;
• connected devices;
• broadband gateways; and
• other postpaid products.

Phone churn isolates the phone base. Total postpaid churn can move differently because non-phone products often have different customer behavior and economics.

Basis points matter

Telecom churn percentages are often small, so year-over-year changes are commonly discussed in basis points.

If churn rises from 0.80% to 0.90%, the change is:

10.90% - 0.80% = 0.10 percentage points = 10 basis points

That is a 12.5% relative increase in the churn rate, but carriers typically describe the change as 10 basis points.

Low churn is not automatically better economics

Retention can be supported by attractive economics, but it can also reflect costly retention offers, device promotions, contract structure, or customer mix.

A carrier might lower churn by increasing handset subsidies or promotional credits. That can help Postpaid Phone Net Additions while raising acquisition or retention costs.

Similarly, churn can rise after price changes or as more customers reach the end of device-financing periods. AT&T explicitly cited customers reaching the end of device financing as one contributor to higher 2025 churn.

Acquisitions and methodology changes can distort comparisons

A newly acquired subscriber base can change customer mix and the denominator. Carriers can also change which products are included in reported phone metrics.

Verizon disclosed in 2025 that it would stop counting its second-number offering in postpaid phone net additions, phone churn, and related phone metrics. That kind of methodology change should be preserved before comparing trend breaks.

Filing examples

T-Mobile reported 2025 postpaid phone churn of 0.93%. AT&T reported 0.90% for 2025. Verizon reported and defined wireless retail postpaid phone churn using phone disconnects over the average phone connection base.

Sources:

• T-Mobile US 2025 Form 10-K
• AT&T 2025 Form 10-K
• Verizon 2025 Form 10-K
• Verizon March 2025 metric reclassification filing

Bottom line

Postpaid phone churn is a retention-rate metric, not net customer growth. Preserve the exact phone population, disconnect and restoration rules, averaging basis, acquisitions, and methodology changes before comparing carriers.

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