Captive portal not showing? Open the WiFi sign-in page

A captive portal is the sign-in page public WiFi puts between you and the internet. When it doesn’t appear, you’re “connected” but nothing works.

Short answer

Open a plain http:// address in your browser (not https) — the network can only redirect unencrypted requests to its sign-in page. If that fails, pause your VPN or custom DNS, forget and rejoin the network, and ask staff for the portal address.

What a captive portal is

The UK NCSC describes captive portals as the login pages present on some public WiFi networks. Your phone detects them by trying to load a test page: if the network answers with something else, the phone shows the sign-in screen. The IETF has standardised a cleaner way for networks to announce their portal (RFC 8908 and RFC 8910), but many venues still rely on redirects.

Universal fixes

Load a plain http:// page. Redirects can’t hijack https, so start from an unencrypted address.
Pause VPN, private DNS hostnames and content blockers until you’re signed in.
Forget the network and rejoin, then wait a few seconds.
Check the date and time on your device; a wrong clock breaks secure pages.
Try another browser or a private window.
Ask staff for the portal address or a code.

Device-specific steps: iPhone · Android.

Is the portal real?

The page address belongs to the venue or its known WiFi provider.
It asks only for what the venue says it needs: terms, an ad, room number, a loyalty login, sometimes an SMS code.
It never asks for your card number for “free” WiFi, your email password or a bank login.
The network name matches the venue’s published name exactly.

SentryFi’s login-page check tells you whether a sign-in page is in the way, which address it comes from and whether it uses HTTPS — and opens it with one tap.

Frequently asked questions

What is a captive portal?

The sign-in page shown by public WiFi before you get internet access — common in hotels, airports and cafés.

Why does http:// help?

The network can redirect an unencrypted http request to its sign-in page; an https request can’t be redirected without a certificate error.

Can a captive portal be fake?

Yes — a copycat network can show its own sign-in page to collect details. Check the network name and the page address, and never enter payment or passwords you use elsewhere.

Sources

Last checked: 2026-10-12. SentryFi is not affiliated with the venues, brands or providers named on this page.