The Galaxy S20 is a 2020 phone with a 4,000 mAh battery and, depending on the region, an Exynos 990 or a Snapdragon 865 chip, and owners on Samsung's community pages have been reporting heat on it since One UI 3. The reports share a pattern: heat after an update, heat while charging, and heat during a camera or a game. After an update the phone spends hours indexing and optimizing, which warms it for a day or two,
so a phone that was hot right after an update and cools afterwards is behaving normally. If it stays hot, the usual remedy owners describe is to wipe the cache partition from recovery mode, which clears the system caches the update left behind, to reset app preferences, and to lift the case. Charging adds heat, and a battery that is now six years old generates more of it. Heat in the camera is normal in 8K and 4K 60 recording.
Differential
Likely causes of “Samsung Galaxy S20 family gets hot or shows a temperature warning”, and how to tell them apart
- 1
Post-update optimization
What separates it The phone is warm for a day or two after an update
How to confirm Leave it alone, plugged in and cool, and check again after two days
- 2
Leftover system cache
What separates it Heat persists after the update settles
How to confirm Wipe the cache partition from recovery mode
- 3
A case and charging
What separates it The phone is hot while charging in a case
How to confirm Remove the case and charge idle on a hard surface
- 4
Camera or gaming load
What separates it Heat during 8K or 4K 60 video and long games
How to confirm Lower the video resolution and take breaks
- 5
A worn battery
What separates it Heat while charging and a short battery life
How to confirm Settings, Battery, and consider a battery service
Before you touch a setting
Record this first — changing settings destroys the evidence
- When the heat happens: idle, charging, camera or games
- Whether it began after an update
- The case and charger in use
- The battery's age and any swelling
Try in this order
0 of 6 completedStop and let it cool
ReversibleUnplug it, remove the case and let the phone cool in a shaded place.
Find what is using the power
ReversibleSettings, Battery and device care, Battery shows the apps that used the most in the last day.
Wipe the cache partition
ReversibleSwitch the phone off, hold Volume Up and the Power or Bixby key to enter recovery mode, choose Wipe cache partition and restart; this keeps your data.
Reset app preferences
ReversibleSettings, Apps, the three-dot menu, Reset app preferences, which does not delete data.
Lower the load
ReversibleReduce the screen's refresh rate to 60 Hz, lower the video recording resolution and close apps you do not use.
Charge sensibly
ReversibleUse Samsung's charger, keep the phone out of the case while charging and do not use it heavily while it charges.
Model-specific
What is true of this model and not of its siblings
- The 2020 chips
- Both the Exynos 990 and the Snapdragon 865 run hot under load, which Samsung's community threads describe repeatedly.
- Recovery mode
- The cache partition option is in the Android recovery menu, not in Settings.
- Support status
- The S20's update window has ended, so heat from software must be handled with settings and the final updates.
Stop boundary
When this stops being a self-service repair
- !If the phone is hot with nothing running after a cache wipe, contact Samsung or an authorized repairer
- !If the battery swells or the back lifts, stop using it
- !A phone that shuts down from heat repeatedly needs a battery check
Evidence ledger
Sources behind this answer
Exact questions
Common questions
Why does my Galaxy S20 get hot after an update?+
The phone optimizes apps after an update, which warms it for a day or two.
Does wiping the cache partition delete my data?+
No, it clears system caches only.
Is S20 heat while charging normal?+
Mild warmth is, a hot phone is not.
Could the battery be the cause?+
On a six-year-old phone, yes.