On August 25, KDDI and povo2.0 began offering 5G SA (Standalone) for the “Voice + Data” plan. The monthly fee is said to be free for now, but wording hinting at a future paid conversion, a SIM card reissue fee, and confusion over unclear naming when migrating to eSIM all drew attention on the thread.
On August 25, KDDI, Okinawa Cellular, and KDDI Digital Life began offering 5G SA for the “Voice + Data” plan under the online-only brand “povo2.0.” A compatible smartphone is required to use the service.
5G SA is a communication method that builds core equipment and base stations exclusively for 5G, without relying on 4G LTE infrastructure. Because it isn’t affected by congestion on the 4G LTE side, it makes high-speed, high-capacity communication easier to use. KDDI is rolling out 5G SA across its entire Sub6-compatible area, putting coverage at over 90%.
Existing povo2.0 users can also sign up, but reissuing a physical SIM card costs a 3,850 yen fee. The eSIM reissue fee is free for the time being. The monthly fee for 5G SA itself is currently free, but it may become an optional paid service in the future.
Source: ascii.jp / Original article here
Even for the same phone model, plenty of SIM-free versions aren't supported.
Voice calls will still run over 4G, right?
Probably just the fee if it eventually becomes paid.
Basically, connecting via 5G SA just means faster speeds — I don't think there's any real downside.
> Are there any downsides to signing up for 5G SA?
One thing that's certain: this isn't just an "optional setting (subscription)" — you need an actual physical SIM swap.
Switching a physical SIM (pSIM) to 5G NSA requires a processing fee.
> Voice calls will still run over 4G, right?
There's no sign of VoNR (Voice over New Radio) anywhere yet.
Same kind of confusion as with the KDDI SIMs that already offer 5G SA… compatibility issues, maybe? We'll have to wait for more reports.
Makes me want to go back to povo.
Well, I've got no complaints with what I have now, so it's fine either way.
Can't wait for 5G SA, huff huff.
It's a top-up purchase system, so au PAY or something similar should work fine too.
Don't you have a credit card?
An all-5G standalone network is something Rakuten Mobile should've been the one to pull off first — getting beaten to it must sting a lot.
yet they're clearly planning to charge extra for it as an option. Greedy.
but once 5G actually spread, talk of charging for it just quietly disappeared.
It was eSIM to eSIM, and I figured the eSIM would just get overwritten, but instead it got installed into an empty slot labeled "Travel" — took me an hour of confusion to figure out what happened.
If you're about to do this, watch out.
If that empty eSIM slot already has a name on it, you won't notice, and you'll have a really rough time.
Assuming it would get overwritten is a bit odd, but
yeah, I see how that kind of trouble could happen.
That's just how iPhone works, isn't it?
The iOS on that device just assigns the new SIM a label from its existing list of candidate names, picking one that isn't already in use.
Also, weren't you asked something partway through that you just missed?
Exactly that.
It's not written in the instructions anywhere.
You can delete it afterward too, but then it shows up under the new eSIM.
If you'd renamed anything in your eSIM folder, it'll be totally confusing.
but I've got 5G data turned off, so this is wasted on me, right?
Also, I give my povo number out to people I'm not actually close with.
And the only compatible devices are ridiculously expensive high-end smartphones.
Even if I wanted to use it, I don't have the environment for it.
UQ supports it, so it shouldn't be a hardware issue.
Background and Key Points
povo2.0 is KDDI’s online-only, no-storefront SIM brand: there’s no monthly base fee, and users instead buy short-term data “topi-ups” to keep the line active, which is why several posters describe it as a backup number they top up every few months for a few hundred yen. KDDI is Japan’s #2 mobile carrier (au), and 5G SA (Standalone) means the network runs entirely on 5G core equipment and base stations rather than anchoring to existing 4G LTE, which is the current mainstream “5G NSA” setup used by most phones today. Rakuten Mobile, Japan’s newest carrier, built its network around all-IP/virtualized architecture and has long positioned itself as the SA pioneer, which is why poster >>21 frames KDDI’s move as an embarrassment for Rakuten.
The thread’s real disagreement isn’t over 5G SA’s usefulness but over whether “free for now” can be trusted: several posters point to the pSIM reissue fee and the vague “may become paid” wording as evidence this is a bait-and-switch, and >>26 explicitly recalls NTT Docomo doing the same “trial, no fee” framing for regular 5G before quietly walking away from the free promise once adoption grew.
What the thread never states plainly is that upgrading isn’t a toggle — it requires an actual SIM swap (paid for physical SIM, free for eSIM), and that voice calls still ride on 4G VoLTE since no VoNR support has been announced, so nothing about call quality changes. Readers may also overestimate coverage: KDDI cites “90% of Sub6 area” covered, but that’s only about 40,000 SA base stations nationwide, and Sub6 signals don’t propagate as far as the low-band spectrum used for standard 4G/5G NSA coverage.
*This article is compiled from excerpts and a summary of the 5ch (Business News+) thread: [Telecom] povo Finally Supports “5G SA” — No Extra Charge for Now.
