Today, Greasby village is a commuter suburb administered by the local authority, Wirral Borough Council. It has no industry and no major shopping centre.

The village's height above mean sea level ("ODN") varies from 24 metres (80 feet) to 30 metres (100 feet).

At Greasby centre (around the Coach & Horses and the Manor restaurant) the national grid reference is SJ253871.
The decimal latitude and longitude position for the Coach & Horses is Lat 53.3762 Long -3.1236
The traditional measurement (degree, minute, second) of that position is Lat 53º 22' 34" N Long 03º 07' 25" W.

The boundaries of Greasby township are:-
west - Greasby Brook
north - Greasby Brook, Arrowe Brook
east - Arrowe Brook, the stream on the west side of Arrowe Brook Lane**, Arrowe Brook Lane
south - Arrowe Brook Lane to Irby Mill pub, Hillbark Road to Greasby Brook

**It is probable that this stream was the original Arrowe Brook prior to the upstream diversion of most of its water in the 1830s to provide the ornamental stream and lake in Arrowe Park.

There are local Sites of Biological Importance (SBI) - Greasby Copse and Ponds at grid reference SJ258866, Upton Bridge Wood aka Millennium Wood SJ265875, Arrowe Brook Farm Ponds at SJ265865 and the former RAF Camp at SJ243877.

Wirral was historically part of Cheshire (long before the Domesday Book in 1086). In 1974 the government changed the boundaries of many counties for administrative purposes. This change was unpopular in Wirral, which was parted from Cheshire and incorporated into the newly formed Merseyside region.

Wirral is still in Vice-County 58 (Cheshire). Vice-Counties (permanently defined geographical areas) were established in 1852 in order to give continuity to historical statistics (e.g. wildlife counts) so that they would be unaffected by politicians who can change political boundaries at whim.