Lenovo ThinkPad T15 Gen 1
Yes. 2 slots, up to 40 GB seen working.
It takes DDR4-2666 laptop-size sticks (SO-DIMM).
- Slots
- 2 SO-DIMM slots
- Type
- DDR4-2666 260-pin SO-DIMM
- Most seen working
- 40 GB in two or more machines; one machine runs 48 GB
- Firmware says
- 32 GB maximum (often wrong, so we show what machines run)
- How sure
- 11 of 18 reports show this layout
Worked out from 18 hardware reports of this laptop. Sources and method. Updated 9 Nov 2026.
Batteries in these laptops report 57 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 18 battery readings. Sources and method. Updated 9 Nov 2026.
IllustrationQuestions
Can I upgrade the RAM in the Lenovo ThinkPad T15 Gen 1?
Yes. 2 slots, up to 40 GB seen working. It takes DDR4-2666 laptop-size sticks (SO-DIMM).
What type of RAM does the Lenovo ThinkPad T15 Gen 1 use?
DDR4-2666 laptop-size sticks (SO-DIMM, 260-pin).
How much RAM can the Lenovo ThinkPad T15 Gen 1 take?
Machines in the reports run up to 40 GB, and one runs 48 GB. The firmware reports a maximum of 32 GB, a figure that is often wrong.
What battery does the Lenovo ThinkPad T15 Gen 1 use?
Batteries in these laptops report 57 Wh, going by 18 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 T15 Gen 1, and the type code starts with 20S6. Other type codes share this name: 20S7.