Overnight Closures on A421 this weekend

National Highways A421 diversion route

National Highways are working on the A421 Westbound between Black Cat junction and Renhold Interchange from Friday 27th February to Monday 2nd March 2026. To allow this work they will be closing the A421 from 9pm on Friday night until 5am on Monday morning.

Please use this planned diversion if you are travelling that route during this period:

  • continue south on A1
  • take A603 towards Bedford.
  • rejoin A421 westbound at Cardington Interchange.

Please inform anyone who may be affected by this closure.Diversion route

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