Statutory basis for TfL, ULEZ and the Congestion Charge regime.
TfL service disruption, National Rail planned engineering, ULEZ, Congestion Charge and Dart Charge alerts
Eight million Londoners and 18 million commuters depend on real-time service disruption data; 1.7 million vehicles a day cross an Ultra Low Emission Zone boundary; the Dart Charge collects 50 million crossings of the Thames a year. 4notify integrates with TfL Open Data, National Rail Darwin, Trainline, ULEZ, Congestion Charge, Dart Charge and the Welsh and Scottish open-data networks to dispatch disruption and zone-charge alerts to the customer's primary channel.
Whereas Transport for London publishes service-disruption open data through the Unified API and TfL Open Data feed, and whereas National Rail Darwin provides the canonical train running information for the Great British rail network, and whereas the Mayor of London administers the ULEZ, the Congestion Charge and the LEZ schemes, the present Notice records the standing dispatch specification for transport-related alerts through 4notify Operations.
Statutory basis for the Congestion Charge and the daily-charge dispatch obligation.
Statutory basis for National Rail Darwin and the train operating company disruption-notification duty.
TfL Open Data subscription + Darwin feed
4notify holds an active TfL Open Data app key and a National Rail Darwin Push Port subscription; latency to the customer typically <60 seconds from the source event.
Per-line / per-station preferences
Customers register their commuter line (e.g. "Northern southbound from Hampstead") or station-pair (e.g. "Cambridge → London Liverpool Street"); only relevant disruptions dispatched.
ULEZ / Congestion Charge / Dart Charge daily reminder
Vehicle-registered customers receive a same-day reminder before midnight if a charge is outstanding; one-tap link to TfL Auto Pay or the Dart Charge portal.
Cross-border (Wales / Scotland / NI)
Translink (Northern Ireland), Transport for Wales and ScotRail disruption feeds covered through the same dispatch envelope.
json
{
"event": "transport.disruption",
"operator": "tfl",
"line": "northern",
"direction": "southbound",
"stations_affected": ["High Barnet", "Edgware", "Mill Hill East"],
"severity": "severe",
"expected_clearance": "2026-05-27T18:30:00+01:00",
"channels": ["push", "sms"],
"template": "tfl_severe_v3"
}TfL Northern southbound: severe delays between High Barnet and Edgware. Expected clearance 6:30pm. Tap for alternative routes via Victoria line at Highbury & Islington.
- TfL Open Data app key valid (rate limits ≤300/min)
- National Rail Darwin Push Port subscription active
- Per-customer line / station preferences captured
- ULEZ / Congestion Charge / Dart Charge vehicle list synced
- Translink / TfW / ScotRail feeds connected for cross-border alerts
4notify is the only A2P platform that combines TfL Open Data, National Rail Darwin Push Port, Translink, Transport for Wales and ScotRail feeds with ULEZ / Congestion Charge / Dart Charge daily reminders and per-line / per-station customer preferences from a single dispatch envelope.
How fast is the dispatch after a service disruption?
P50 latency from TfL Open Data source event to dispatch on the customer handset is under 60 seconds; National Rail Darwin Push Port can be slower (90-120s) due to upstream propagation.
Can I subscribe to ULEZ alerts without owning a vehicle?
Yes — fleet operators and hire-car companies subscribe by registration number; private customers subscribe by their own VRM in TfL Auto Pay.
What about planned engineering vs unplanned disruption?
Planned engineering works are dispatched on a 14-day, 7-day and 1-day cadence; unplanned disruption fires within the 60-second target.
Start free
14 days. No card. UK-based support through the working week.