Heathrow Terminal 4 is now more or less back to normal business although prospective passengers should check with their air carrier to confirm which terminal for an individual flight.

The Elizabeth Line runs in both directions between T3 and T4 but only at present every 30mins, and is free.  

The Piccadilly Line has 10mins between trains only one way from T4 to T3.  It is a different station at T4, a 5min walk from the Elizabeth Line.  

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