Globally, people live predominantly near the coast: half of the world's population is to be found less than 200 km from the sea and more than a quarter is 50 km. The Channel region is a good example of this attraction to coastal and sub-coastal areas as, with almost 50 million inhabitants, representating more than 10% of the European Union's population, it has a density of more than 500 residents per km². The latter is more than four times the Community average, due to the concentrated settlement of both the area's coastline and immediate hinterland, and nowhere does the density fall below 100 inhabitants per square kilometre.

The weight of the two regional capitals clearly has a considerable impact on these exceptional densities; there are more than 29 million residents in the Ile-de-France region and Greater London, contributing 59% of the region's total. Even without considering the Paris region, the two sides of the Channel zone still count for over 38.5 million people, the same population as Poland. However, the eccentric geographical position of the two global cities in relation to the whole Channel region, as well as the higher population densities of northern France and southeast England, affords a first indication of an east-west imbalance. A decreasing density gradient is evident from the higher populations of the London conurbation and the Paris region in the east to the more dominantly rural areas of the western peninsulas, where densities can fall below 30 inhabitants per km² in the wetter Atlantic uplands (Bodmin and Dartmoor in Cornwall and Devon, monts d'Arrée in Finistère).

This contrast in part cuts across the more urbanised east of the region where the two metropolitan capitals are located, in addition to numerous other urban areas (Lille, the old coalfield basin of Nord-Pas-de-Calais, the southern English coastline between Hastings and Bournemouth) and heavily settled growth corridors (Seine, Oise and Loire valleys, southeast England). The outward spread of London, the succession of ports and holiday resorts along the south coast of England, and a generally higher average population density in England than in France, has introduced a second imbalance between the two coastlines: the English littoral (with 730 inhabitants par km²) is almost three times as populated as its French counterpart (with 255 per km²).