T-Mobile (TMUS) Q4 2025 earnings review

Top-Line Boom, Bottom-Line Bust

T-Mobile delivered a paradoxical quarter. Revenue growth accelerated to nearly 11% YoY, fueled by the UScellular acquisition and best-in-class customer adds. However, this growth came at a steep price: Net Income plunged 30% and EPS fell 27% as integration costs, severance, and rising service expenses hammered profitability. While the customer growth engine remains unrivaled (962k phone adds), the 'un-carrier' is currently struggling to convert that volume into bottom-line earnings growth, though FY26 guidance suggests a return to EBITDA expansion.

🐂 Bull Case

Unrivaled Customer Velocity

The growth engine is firing on all cylinders. T-Mobile added 962k postpaid phone customers in Q4 alone—leading the industry. Total broadband adds (558k) also accelerated, proving the company can win share even while digesting a major acquisition.

2026 Outlook Promises EBITDA Acceleration

Management guided FY26 Core Adjusted EBITDA to $37.0–$37.5B, implying ~10% growth over FY25. This suggests the current margin compression is temporary 'indigestion' from M&A integration rather than a structural problem.

🐻 Bear Case

Earnings Quality Deterioration

Net Income collapsed 30% YoY. Even excluding the $293M severance charge, profitability is under pressure. Cost of services surged 23% and SG&A jumped 23%, far outpacing revenue growth. The 'profitable growth' narrative has stalled.

Churn is Creeping Up

Postpaid phone churn spiked to 1.02% in Q4, up from 0.89% in Q3 and 0.92% a year ago. Management cites 'higher industry switching,' but this breaks the trend of steady improvement and warrants close monitoring during the integration phase.

⚖️ Verdict: ⚪

Neutral. Top-line execution is flawless, but the cost of buying growth (UScellular/Fiber) is temporarily crushing GAAP earnings. The thesis holds only if FY26 guidance delivers the promised 10% EBITDA ramp.

Key Themes

CONCERN NEW 🔴

Merger Indigestion Hits Margins

The UScellular and fiber acquisitions have introduced significant noise and cost. Cost of services (ex-D&A) skyrocketed 23% YoY to $3.3B, and SG&A rose 23% to $6.6B. Consequently, Net Income margin compressed from 13.6% last year to 8.6% this quarter. While synergies are promised, the immediate reality is a sharp reversal in operating leverage.

CONCERN NEW 🔴

Churn Spike Alert

Postpaid phone churn hit 1.02%, crossing the psychological 1% threshold for the first time in recent quarters. While seasonal trends and industry switching are cited, a 10bps sequential jump suggests potential friction from integrations or aggressive competitive offers. This breaks T-Mobile's multi-year streak of churn reduction.

DRIVER 🟢🟢

Dominant Customer Acquisition

T-Mobile continues to embarrass peers on growth. Q4 Postpaid Net Adds (2.4M) and Phone Net Adds (962k) accelerated sequentially and YoY. The machine is not slowing down: FY26 guidance projects another 900k-1M postpaid account additions. The widening gap between T-Mobile's intake and competitors is the strongest pillar of the bull case.

DRIVER 🟢

Broadband Juggernaut

The broadband segment (FWA + Fiber) remains a key growth vector, adding 558k customers in Q4 (vs 506k in Q3). With 9.4M total broadband customers, T-Mobile has successfully diversified beyond mobile. The acceleration in adds proves the addressable market is not yet saturated.

THEME ⚪

Capital Return Machine

Despite earnings pressure, cash flow remains robust enough to support shareholder returns. T-Mobile repurchased $2.5B in shares and paid $1.1B in dividends in Q4. FY25 total returns hit $14.0B. The authorization allows for another $14.6B through 2026, providing a floor for the stock price.

Other KPIs

Postpaid Service Revenue $15.4 billion

Accelerating. Growth hit +13.9% YoY, up from +10.7% for the full year. This is the cleanest indicator of organic health + acquisition layering. It confirms that the top-line thesis is intact.

Adjusted Free Cash Flow (FY25) $18.0 billion

Stable. Grew 6% YoY. While solid, this trails the 11% service revenue growth, highlighting the cash costs of integration and capital expenditures ($10B). Q4 FCF actually declined 13% sequentially.

Core Adjusted EBITDA Margin 45.2%

Reversing. Margin compressed from 47.6% in Q3 25 to 45.2% in Q4. This 240bps drop reflects the immediate dilutive impact of UScellular and Fiber acquisitions before synergies are realized.

Guidance

FY26 Core Adjusted EBITDA $37.0 - $37.5 billion

Accelerating. Midpoint implies ~10% growth vs FY25 ($33.9B). This is the critical 'prove it' number—management is promising that the Q4 margin compression is temporary and synergies will kick in fast.

FY26 Adjusted Free Cash Flow $18.0 - $18.7 billion

Decelerating. The midpoint ($18.35B) implies only ~2% growth over FY25 ($18.0B). Despite the projected 10% EBITDA boom, cash flow is barely growing. This suggests heavy cash costs for integration or working capital drags are expected to persist through 2026.

FY26 Cash CapEx ~$10.0 billion

Stable. Flat vs FY25 ($9.96B). This indicates the network buildout is steady, and the muted FCF growth isn't due to a sudden spike in infrastructure spending.

Key Questions

The EBITDA-FCF Disconnect

You are guiding for ~10% EBITDA growth in 2026 but only ~2% Free Cash Flow growth. With CapEx flat, where is the $3 billion delta going? Is this all merger integration cash costs?

Churn Normalization

Churn broke the 1% ceiling this quarter. How much of this is strictly UScellular integration friction vs. a structural change in the competitive environment, and when do you expect to return to sub-0.90% levels?

Expense Baseline

SG&A and Cost of Services both jumped 23% this quarter. Is Q4 the new run-rate baseline for the combined entity, or were there significant one-off integration expenses booked in Q4 that will fall off in Q1?