How to Replace Cat Flap Batteries (SureFlap, PetSafe & Closer Pets)

• SureFlap Microchip / DualScan / Connect: 4 × AA alkaline
• SureFlap Pet Door (large): 4 × C alkaline
• PetSafe Microchip Cat Flap: 4 × C alkaline
• PetSafe Staywell: 4 × AA alkaline
• Closer Pets MPC-11 / MPC-21: 4 × AA alkaline
• Pet-Tek G-SDDW / G-SDDB: No batteries (manual flap)

Always use brand-new alkaline batteries. Never rechargeables — they output 1.2V instead of the 1.5V the flap needs, and the unit will report 'low battery' immediately.

1. Lock the flap to 4-way locked so your cat doesn't try to come through mid-job
2. Remove the battery cover on the inside of the flap (the side facing your kitchen). On standard SureFlap it's a single screw at the bottom
3. Pop the batteries out — note the +/- orientation, it varies by model
4. Wait 30 seconds before fitting new batteries — this clears any residual charge and prevents memory glitches
5. Fit 4 fresh alkaline AAs, replace the cover
6. The flap should beep once and the indicator light should flash. Your cat's memory is preserved — no need to re-programme.

If the flap doesn't beep, try one more set of fresh batteries (sometimes you get a dud out of the pack).

PetSafe Microchip flaps use 4 × C-cell alkaline which last around twice as long as SureFlap's AAs (typically 12 months).

1. Lock the flap
2. Unscrew the battery cover on the inside face — usually 2 small Phillips screws
3. Replace all 4 C cells together (don't mix old and new)
4. The flap beeps to confirm — memory is retained

Tip: C-cell batteries are bulkier and pricier than AAs. Buy a 4-pack of Duracell C or Energizer C and they'll typically last a full year.

The Closer Pets microchip range uses 4 × AA alkaline in a slide-out cassette.

1. Lock the flap
2. Slide the battery compartment cover downward (no screws)
3. Lift out the cassette, replace all 4 AAs
4. Slide the cassette back — flap beeps once to confirm

Closer Pets batteries typically last 9–12 months.

Don't use rechargeable batteries. Eneloops, supermarket rechargeables and other NiMH cells output 1.2V per cell. Microchip cat flaps need 1.5V per cell to power the antenna properly. With rechargeables, the flap may seem to work briefly but will fail to read chips reliably, drain quickly, or refuse to start at all.

Also avoid: mixing old and new batteries, mixing brands, or using 'long-life' lithium AAs (some flaps misread the voltage). Standard alkaline — Duracell, Energizer, Panasonic, Amazon Basics — is exactly what you want.

Set a calendar reminder for annual replacement. Even if the flap seems fine, replace batteries every 12 months — it prevents the slow voltage drop that causes chip-reading failures.

If your cat uses the flap heavily (10+ trips a day), every 6–9 months is safer. SureFlap Connect models (with wireless) need changing every 3–6 months.

For more troubleshooting, see our guide on SureFlap not reading microchip or browse our full brand comparison.