A major signalling issue is causing congestion and delays of up to 90 minutes, according to Iarnród Éireann.

At 12:52pm they posted on X saying: "Major signalling issue between Lansdowne and Donabate. Staff are working to rectify this matter."

They said that due to the issue, there will be major delays, which started at 25 minutes but has since been updated to 90 minutes.

Their latest update said: "Services are beginning to resume between Donabate and Lansdowne Rd in both directions following a major signalling issue. Delays of up to +90mins Alterations will be made to aid service recovery. Knock-on delays can be expected due to severe congestion.

Iarnród Éireann said the affected services include:

-DART

-Belfast

-Northern Commuter

-Sligo

-Rosslare

-Maynooth

-M3 Parkway/Hazelhatch

UPDATE: Services are beginning to resume between Donabate and Lansdowne Rd in both directions following a major signalling issue.

Please note:

Delays of up to +90mins

Alterations will be made to aid service recovery

Knock-on delays can be expected due to severe congestion. -AD https://t.co/Ih6UckojOM— Iarnród Éireann (@IrishRail) August 20, 2026

Due to the congestion, other lines will be impacted, but Irish Rail says services are resuming between Donabate and Lansdowne Road in Dublin in both directions.