A captive portal is a web page that public WiFi users see before being granted internet access — typically used to authenticate users, accept terms, and capture data such as email or social-login identity.
A captive portal is the splash page that appears the first time you connect a phone or laptop to a public WiFi network — for example in a coffee shop, hotel lobby, airport, or pub. Before granting internet access the network forces the device to load a specific URL, where the user can sign in, enter an email, accept terms, watch a short ad, or use a voucher code.
When a device connects to a WiFi network with a captive portal, the access point or router intercepts the first HTTP/HTTPS request and redirects the browser to the portal page. Modern operating systems (iOS, Android, Windows, macOS, ChromeOS) all detect this redirect automatically and pop up a "captive network assistant" mini-browser, which is why a WiFi sign-in page often appears without you clicking anything.
Once the user completes the portal flow — entering an email, signing in with Facebook or Google, or accepting the terms of service — the access point adds the device's MAC address to an allow-list and the device is granted full internet access for a configurable session length (often 24 hours, then re-prompt).
Captive portals turn free guest WiFi from a cost centre into a marketing channel:
A traditional WPA2 / WPA3 password protects the network from random outsiders, but it doesn't tell you anything about who connects. A captive portal layered on top of an open or password-protected SSID gives you the user's identity (email or social) without sacrificing convenience — guests can still hand the password to staff if you offer one. The two approaches complement each other.
Almost every business-grade WiFi system supports captive portals: Ubiquiti UniFi, TP-Link Omada, Cisco Meraki, Aruba Instant On, MikroTik, Ruckus, Cambium, DrayTek, Engenius and many others. Pure consumer routers usually don't, which is why hospitality venues invest in a dedicated AP rather than the ISP-supplied router.
For a complete walkthrough of setting one up, see the UniFi captive-portal setup guide and the TP-Link Omada captive-portal setup guide.
WiFi marketing is the practice of using a venue's guest WiFi network — typically via a captive portal — to capture customer data and deliver follow-up communications such as automated emails, SMS, review requests, and loyalty offers.
Guest WiFi is a public, internet-only WiFi network a business offers to customers, separate from its private back-office network, typically secured by a captive portal that requires sign-in.
WiFi data capture is the process of collecting customer information — typically name, email, mobile number or social-login identity — when a guest connects to a venue's WiFi via a captive portal.
WiFi email capture is the technique of collecting a guest's email address as a condition of free WiFi access, typically through a captive portal's sign-in form, so the venue can send marketing communications afterwards.
Capture guest emails, run automated email/SMS campaigns, and grow Google reviews — all from your existing WiFi.