Samsung Galaxy S26 Ultra charging speed Review & Buying Guide: Features, Trade-Offs & Value

② Expert Analysis

Every figure below is labelled by origin. No charging measurement was produced for this review.

The claim, and why the lab beating it is good news with a footnote

Samsung’s claim is deliberately narrow: up to 75% in around 30 minutes (manufacturer claim). It carries the word “around”, it stops at three-quarters, and it says nothing about a full charge. GSMArena’s laboratory test of this exact model, run with Samsung’s own 60W charger, recorded 51% at 15 minutes, 84% at 30 minutes and a full charge in 43 minutes (third-party lab results) — nine points ahead of Samsung’s claim at the half-hour mark, and a full charge well under an hour. That direction of error is welcome, but the laboratory is explicit that the published curve is its best run and that repeat runs varied by a few percentage points and minutes. The honest expectation, then, is not “43 minutes, every time” but “around four-fifths in half an hour, full in roughly three-quarters of an hour, with run-to-run variation”. A buyer who treats the best run as a guarantee will be disappointed on an unlucky day; a buyer who treats Samsung’s 75% claim as the ceiling will be pleasantly surprised most days.

Not proprietary — and why that matters more than the wattage

The most useful finding in the laboratory’s test is not a percentage but a standard. Super Fast Charging 3.0 on this model runs over standard USB Power Delivery with a 3A/20V PPS profile (third-party lab finding), so any 60W USB-PD charger supporting that profile should deliver the fastest charging the phone is capable of — and the laboratory confirmed it, getting similar times from a third-party 67W charger. The practical consequence is that the fastest setup does not require Samsung’s own brick: it requires the right profile. A 60W charger without the PPS profile, or a high-wattage charger that negotiates a lower profile, will not reproduce the laboratory’s curve, and neither will a cable rated below 3A — though the 3A cable supplied with the phone is enough, since the laboratory measured current never rising above 3A. Samsung’s own 60W charger is sold without a cable, per the laboratory’s note, so a buyer adding Samsung’s brick still needs the in-box cable. The S25 Ultra’s 45W ceiling and Super Fast Charging 2.0 name belong to the previous generation and must not be quoted here.

The wireless lane — 25W, with a case-shaped condition

Wireless charging improves from the previous generation’s 15W to 25W (manufacturer specification), but the headline wattage is only half the story. Samsung does not claim built-in magnets for this model, and GSMArena’s review confirms the phone lacks them: the 25W Qi 2.2 lane is reached with a magnetic case that aligns the charging coil properly, while Samsung’s own FAQ recommends a Magnet Case whose ring provides that alignment. Without the case, alignment is by hand and the top wireless speed is not assured. That is a real, recurring cost of the wireless setup — the case, not just the pad — and it is also the trap for buyers coming from phones with magnets in the body: the snap-on feel they expect will not be there until the case supplies it. The base S26 models’ 20W wireless figure is never this model’s figure, and neither is any “built-in Qi2 magnets” claim.

Reverse charging and battery protection — small lanes, honestly labelled

Reverse wireless charging at 4.5W (manufacturer specification) is a convenience lane for earbuds and watches, not a way to rescue another phone: GSMArena notes the phone may not be able to initiate charging of all types of devices, and 4.5W is slow by any measure. Battery protection, as described in GSMArena’s review of this model, offers three behaviours — Basic, which avoids holding at 100% during long plug-in periods; Maximum, which caps charging at a chosen 80%, 85%, 90% or 95%; and Adaptive, which applies the Maximum ceiling overnight and switches to Basic before waking — plus separate toggles to turn off fast charging for wired and wireless. These are review-described settings, not Samsung specifications lines, but they matter to the charging story because a phone capped at 80% will look “slow to full” to a buyer who set the cap and forgot it. Check the protection setting before blaming the charger.

When charging slows down in real life

Three slowdowns are normal and should not be diagnosed as faults. Charging speed falls as the battery fills — the laboratory’s own curve shows the power dialling down from 51–53W to around 40W — so the last stretch always takes longer than the first-half pace suggests. Heat throttles charging, so a phone charging in sun, under a thick case on a warm pad, or while gaming will slow itself down. And a worn battery charges differently from a new one; Samsung’s published battery story for this model gives no typical-use figure to measure against, only the 31-hour video-playback claim under lab conditions, so a battery that no longer matches its new behaviour needs assessment rather than a new charger. What is not normal is no charge at all, charge only at one angle, or a port that will not hold a cable — those are the symptoms the repair guides below address.

Before calling it slow

Run the checks in order: the charger’s profile (60W USB-PD with 3A/20V PPS for the fastest wired lane), the cable (the supplied 3A cable, in good condition), the wireless setup (a Qi2 magnetic case if 25W wireless is expected), the battery-protection setting (a forgotten 80% cap explains many “won’t fill” complaints), and the battery’s health. If all five check out and the phone still will not charge, the fault is in the phone, not the setup — and the port and battery guides below are the next step.