Walhain has 7,187 inhabitants spread over 38.1 km². Residents have an average age of about 38, and 50.2% are women. Home ownership is 76%, and average net income is €21,926 per person per year. The population is 96.1% Belgian, 1.3% French, 0.5% Italian, 0.4% Romanian, 0.2% Spanish, 0.2% British, 0.2% Portuguese and 1.2% other nationalities. The local housing stock is mostly made up of houses: they represent 93.4% of dwellings, compared with 6.6% for apartment buildings. Dwellings average 6.4 rooms, and buildings date on average from around 1935.
The wider building mix consists of 56.8% open-type houses, farms and castles, 26.1% semi-closed houses, 7.2% closed-type houses, 6.4% buildings and apartment blocks, 2.6% other types of buildings and 0.9% commercial houses. Walhain currently has 0 houses for rent, so there is no current asking-rent range for houses. For context on the local market, 9 houses are listed for sale, averaging €597,000, with asking prices from €299,000 to €1,500,000.
Walhain’s main roads include the N4, N243a, N243 and N273. The A4 / E411 - E25 motorway entrance is 5 minutes by car from the centre, while the A15 / E42 entrance is 17 minutes away. The former runs towards Brussels, Namur, Arlon and Luxembourg City; the latter connects La Louvière, Charleroi, Namur and Liège. There are 7 bus lines with stops in the commune, including TEC lines 24, 25, 34, 52 and 543. The nearest railway stations to the centre are Chastre, Ernage, Blanmont, Gembloux and Mont-Saint-Guibert.
Childcare and schooling options include 2 nurseries, 4 nursery schools and 4 primary schools; Walhain has no secondary school. Named examples include Le Petit Favia, Les P'Tits Loups, Ecole Fondamentale Communale and Ecole Fondamentale Autonome Nil-Saint-Vincent. The commune has 2 Louis Delhaize supermarkets, 1 Intermarché and 1 Delhaize. There is no known EV charging station, shared-bike scheme or shared-car service in Walhain. Brussels South Charleroi Airport is 27 minutes away by car and 124 minutes by public transport.