Mail delayed following earthquake

New Zealanders are sending fewer letters and more emails.

New Zealand Post is warning that some mail will be delayed in areas hit by this week's earthquakes.

It said this morning that post and courier services "have largely resumed".

However, there will no deliveries in Kaikoura and some surrounding towns. Deliveries in Blenheim are also running late but are expected to be made this afternoon.

Some post box centres in central Wellington remain closed and flooding in the capital today means posties will be unable to make deliveries in parts of Lower Hutt and Porirua.

"Inter-Island mail and parcels are being processed and delivered but there is a reduced Cook Strait ferry schedule and trucks are taking a slower route through the Lewis Pass," NZ Post said this morning.

"Most overnight priority products (CourierPost and FastPost) going between the North and South Islands will meet delivery targets, but will arrive late in Blenheim. Standard Mail, Economy Courier and Parcel Post items being sent from the North Island to the West Coast and areas south of Christchurch could take an extra day," NZ Post said

Post shops in Kaikoura, Blenheim, Waiau, the Christchurch suburb of Riccarton, and some Wellington and Lower Hutt branches are closed while buildings are checked.