Styluses & pens
Microsoft Surface Pen (AAAA) battery
1 × 1.5V alkaline cell
Replaceable Surface Pens take one AAAA in the body. Identify your pen first — Slim Pen / Slim Pen 2 have no replaceable cells. Two side-button pens may also need two size 319 coin cells in the cap (separate from AAAA).
How to replace it
| How to open | Identify your Surface Pen first (Microsoft Support: Identify your Surface Pen). No-clip: pull the top straight out, replace AAAA with (+) toward the tail, push halves together. Single side-button: twist cap ~30°, pull straight out, replace AAAA with (+) toward the tail, realign guide bump, reseat. Two side-buttons: unscrew top from bottom, replace AAAA with (+) toward the writing tip, screw closed. Two-button pens may also need 2× size 319 in the cap (separate from body AAAA). |
|---|---|
| Orientation | Follow Microsoft generation steps — (+) toward tail for no-clip / single-button; (+) toward tip for two side-button pens |
| Re-pair after change | Yes |
| Notes | Two side-button pens may need re-pairing after battery change. Cap Bluetooth cells are size 319 coin cells — not AAAA. |
| Access | Tool-free |
Important
- Surface Slim Pen and Slim Pen 2 do not have replaceable batteries — they are rechargeable. Do not buy AAAA for Slim Pen.
- AAAA (body) is not the same as size 319 (cap Bluetooth cells on two side-button pens).
- Confirm generation with Microsoft’s Identify your Surface Pen guide before buying cells.
Sources
Helpful for this device
Optional tools for opening, testing or charging — separate from the battery answer.
- Fluke 101 Digital Multimeter
Accurate open-circuit voltage and basic electrical checks
- Klein Tools MM400 Multimeter
General DC voltage checks including battery terminals
- Digital multimeter
Measure open-circuit voltage and general electronics checks
New battery but still not working?
A fresh 1 × AAAA should restore Microsoft Surface Pen (replaceable AAAA) if the battery was the problem. Work through the checks below before replacing the device.
- Check orientation
Confirm the cell is seated correctly: Follow Microsoft generation steps — (+) toward tail for no-clip / single-button; (+) toward tip for two side-button pens
- Check the battery type
This device needs 1 × AAAA (alkaline). Rechargeable cells are not supported for this device. Same size does not always mean the same battery.
- Check known model-specific issues
Re-pairing or a short reset may be required after a battery change. Surface Slim Pen and Slim Pen 2 do not have replaceable batteries — they are rechargeable. Do not buy AAAA for Slim Pen. AAAA (body) is not the same as size 319 (cap Bluetooth cells on two side-button pens). Confirm generation with Microsoft’s Identify your Surface Pen guide before buying cells.
- Confirm the battery itself
Try a known-good fresh cell of the exact code listed above.
- Still not responding?
If a correct, fresh battery installed properly does not restore the device, the fault may be elsewhere — the device may need service or replacement.
Replacing the device?
Microsoft Surface Pen (replaceable AAAA) is still sold new. Only consider a replacement if the checks above did not help.
Need to replace the device?
Microsoft Surface Pen (replaceable AAAA) is still sold new. Only buy another if a fresh battery and the checks above did not help.