There's a pair of escalators between the mainline concourse, opposite platform 5 and the Underground concourse. The left-hand one is normally the one you need.
There's a pair of escalators from the London Street concourse to the Bakerloo Line. The right-hand one is normally the one you need.
There is no escalator access to the Circle and District lines.
PADDINGTON UNDERGROUND STATION
© 2008, Terry Robinson