Spark 40 5G vs Redmi Note 15 5G

Phone 1

Phone 2

Winner

Xiaomi Redmi Note 15 5G

Lifespan decides this one: the Redmi Note 15 5G is supported until Dec 2029 at $6.03 per month of safe use, while the Spark 40 5G runs out in Aug 2028 ($4.40/month). On a which-lasts-longer question, that's not a tie — it's the whole answer.

Value Score: Spark 40 5G 72 · Redmi Note 15 5G 71 — methodology

The lifespan decider

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

Tecno Spark 40 5G $115

Buy with care$4.40/mo

2025◆ Buy-by Aug 20262028

Xiaomi Redmi Note 15 5G $250

Safe to buy$6.03/mo

2025◆ Buy-by Dec 20272029

Category by category

Display

Spark 40 5G 70Redmi Note 15 5G 80

The Redmi Note 15 5G's screen is the better one — 6.77-inch amoled, fhd+, 120hz, 3200 nits peak.

Performance

Spark 40 5G 55Redmi Note 15 5G 48

The Spark 40 5G's MediaTek Dimensity 6400 is simply the faster chip.

Camera

Spark 40 5G 55Redmi Note 15 5G 67

The Redmi Note 15 5G has the stronger camera system (2 real rear lenses vs 1).

Battery

Spark 40 5G 100Redmi Note 15 5G 90

6,000mAh vs 5,520mAh — the Spark 40 5G lasts longer between charges.

Software longevity

Spark 40 5G 31Redmi Note 15 5G 49

The Redmi Note 15 5G is supported until Dec 2029 — 15 months longer than the Spark 40 5G.

Value

Spark 40 5G 72Redmi Note 15 5G 71

Pound for pound, these two are equally good deals.

Full spec table

Spec	Spark 40 5G	Redmi Note 15 5G
Price (street)	$115	$250
Display	6.75-inch IPS LCD, HD+, 120Hz	6.77-inch AMOLED, FHD+, 120Hz, 3200 nits peak
Chipset	MediaTek Dimensity 6400	Qualcomm Snapdragon 6 Gen 3
RAM	4GB/8GB	8GB
Storage	128GB/256GB	256GB/512GB
Battery	6,000 mAh	5,520 mAh
Charging	18W wired	45W wired
Rear cameras	50MP main	108MP main, 8MP ultra-wide
Dimensions	167.7 × 77.9 × 8 mm	164 × 75.4 × 7.4 mm
Weight	194 g	178 g
Water resistance	Not rated	IP66
Supported until	Aug 2028	Dec 2029

Spark 40 5G full verdict →Redmi Note 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.