Lenovo ThinkPad T431s
Yes. One slot, up to 4 GB seen working.
It takes DDR3-1600 laptop-size sticks (SO-DIMM).
- Slots
- 1 SO-DIMM slot
- Type
- DDR3-1600 204-pin SO-DIMM
- Most seen working
- 4 GB in two or more machines; one machine runs 8 GB
- Firmware says
- 8 GB maximum (often wrong, so we show what machines run)
- How sure
- 4 of 4 reports show this layout
Worked out from 4 hardware reports of this laptop. Sources and method. Updated 9 Nov 2026.
Batteries in these laptops report 47 Wh.
That is the design capacity the batteries themselves report, and the label can read 1 to 3 Wh higher. Other pack sizes may have shipped, so check the capacity printed on yours before you order.
From 3 battery readings. Sources and method. Updated 9 Nov 2026.
IllustrationQuestions
Can I upgrade the RAM in the Lenovo ThinkPad T431s?
Yes. One slot, up to 4 GB seen working. It takes DDR3-1600 laptop-size sticks (SO-DIMM).
What type of RAM does the Lenovo ThinkPad T431s use?
DDR3-1600 laptop-size sticks (SO-DIMM, 204-pin).
How much RAM can the Lenovo ThinkPad T431s take?
Machines in the reports run up to 4 GB, and one runs 8 GB. The firmware reports a maximum of 8 GB, a figure that is often wrong.
What battery does the Lenovo ThinkPad T431s use?
Batteries in these laptops report 47 Wh, going by 3 reports. Other pack sizes may have shipped, so check the capacity printed on yours.
Is this my laptop?
Check the label on the bottom. It should say ThinkPad T431s, and the type code starts with 20AA. Other type codes share this name: 20AC.