Battery Drain After SIM Change
 

I recently switched from T-Mobile to US Mobile and added an e-sim.

Since the change, my iPhone 13PM battery has been draining very quickly, it’s definitely abnormal.

I removed the old TMobile physical sim and it’s still draining. I switched between a couple US Mobile networks and removed any unused e-sims - still draining.

Any ideas?

Shouldn't make a difference, however, a couple of things do come to mind... the broadcast frequencies used by US Mobile might not be some of the more "energy efficient" (eg, they don't penetrate physical infrastructure as well). It might also cause your iphone to scan for towers more often.

Not sure if this is a feature iphones have (modern Android do....at least stock and Samsung ones), but shortly after using my phone for a while (few weeks), I was asked if I wanted to change charging styles (eg, re-calibrate to charge to 80% to preserve battery life).... doing the 80% is definitely noticeable. That said, I was asked explicitly about this "feature", it wasn't forced on me. The %% goes down noticeably faster (at least for me).

US Mobile uses Verizon, T-Mobile or ATT networks. I can’t remember if it happened when I first switched or if it got really noticeable when I switched from their Verizon network to the ATT network and received a new eSIM.

One other thought… were you connecting to 5G or mm-wave networks previously? You said you had a legacy in the other thread.

5G *can be* very energy-intensive, I’m not sure what factors contribute. I find my 13 mini loses almost double the battery using 5G over LTE (I’m outside the US), so I’ve set my usage to LTE max (or 3G/2G), not 5G On or 5G Auto.

Or, perhaps it’s just time to replace the battery; it’s nearing 4 years now since the 13 released. I’m in the 70% range myself.

The only change to the phone was activating a USM eSIM on Verizon, then having that eSIM replaced with a new one for ATT - then finding and removing the physical Tmobile SIM was still in the tray