P3 Ultra 5G vs Redmi 15 5G

Phone 1

Phone 2

Winner

Xiaomi Redmi 15 5G

Lifespan decides this one: the Redmi 15 5G is supported until Aug 2029 at $4.81 per month of safe use, while the P3 Ultra 5G runs out in Mar 2029 ($9.49/month). On a which-lasts-longer question, that's not a tie — it's the whole answer.

Value Score: P3 Ultra 5G 74 · Redmi 15 5G 75 — methodology

The lifespan decider

When specs are close, support length decides it — this is what each phone costs per month of safe use.

Realme P3 Ultra 5G $315

Buy with care$9.49/mo

2025◆ Buy-by Mar 20272029

Xiaomi Redmi 15 5G $180

Safe to buy$4.81/mo

2025◆ Buy-by Aug 20272029

Category by category

Display

P3 Ultra 5G 70Redmi 15 5G 70

Both displays are effectively the same class.

Performance

P3 Ultra 5G 74Redmi 15 5G 46

The P3 Ultra 5G's MediaTek Dimensity 8350 Ultra (4nm) is simply the faster chip.

Camera

P3 Ultra 5G 67Redmi 15 5G 55

The P3 Ultra 5G has the stronger camera system (2 real rear lenses vs 1).

Battery

P3 Ultra 5G 100Redmi 15 5G 100

Battery capacities are close enough not to decide this.

Software longevity

P3 Ultra 5G 40Redmi 15 5G 45

The Redmi 15 5G is supported until Aug 2029 — 4 months longer than the P3 Ultra 5G.

Value

P3 Ultra 5G 74Redmi 15 5G 75

Pound for pound, these two are equally good deals.

Full spec table

Spec	P3 Ultra 5G	Redmi 15 5G
Price (street)	$315	$180
Display	6.83-inch AMOLED, 1.5K, 120Hz, up to 1500 nits peak, Gorilla Glass 7i	6.9-inch IPS LCD, FHD+, 144Hz, 850 nits peak
Chipset	MediaTek Dimensity 8350 Ultra (4nm)	Qualcomm Snapdragon 6s Gen 3
RAM	8GB/12GB	4GB/6GB/8GB
Storage	128GB/256GB/512GB	128GB/256GB
Battery	6,000 mAh	7,000 mAh
Charging	80W wired (100% in 47 min), 5W reverse	33W wired, 18W reverse wired
Rear cameras	50MP main, 8MP ultra-wide	50MP main, 2MP depth
Dimensions	163.1 × 76.9 × 7.4 mm	169.5 × 80.5 × 8.4 mm
Weight	183 g	217 g
Water resistance	IP68/IP69	IP64
Supported until	Mar 2029	Aug 2029

P3 Ultra 5G full verdict →Redmi 15 5G full verdict →Longevity master board →

Scores and verdicts are computed from our verified database — see exactly how. Specs from manufacturer documentation; prices reflect major US retailers.