Despite agreement on an end to the unofficial strikes, postal services are expected to remain disrupted for several weeks.
Thousands of workers in London and other regional centres returned to work on Monday, and a full complement of staff is expected by Tuesday.
Royal Mail advice is that customers can now start posting letters as normal, but should be aware that it will take two or three weeks to clear the backlog.
In central London, thousands of post boxes which had been sealed up are starting to be reopened. The process is expected to take a couple of days.
Special Delivery services, which have been suspended in some areas, are due to resume on Tuesday.
Below are a list of the areas which have been affected by the action. At the bottom of the page is a list of main mail centres which have been unaffected.
Post office branches all remained open, and Parcelforce parcel services were unaffected.
- Central London: EC1-4, WC1, WC2
West London: all W postcodes
North London: N1-3, N5-8, N10-13, N16, N19, N21
North West London: NW1- 6, NW8-11
South West London: SW1-2, SW4-6, SW8-20
South East London: SE1-5, SE7-10, SE13-16, SE19-28
East London: E1, E3-4, E6, E10-14, E16-17
Special Delivery items are not being accepted in any of the above London postcodes for the time being, but will resume from Tuesday.
Post boxes are being unsealed in all of the above London postcodes. This process may take a couple of days to complete.
- Ilford: IG1-6, IG8, IG11
- Romford: RM1-2, RM4, RM7, RM9, RM12, RM13, RM15
- Southend: SS3-5, SS9, SS13-17
- Colchester: CO1-4
Post boxes are being unsealed in all the above IG and RM postcodes.
Special Delivery items were suspended in IG, SS, CO, CM or RM postcodes but will resume on Tuesday.
- Dartford: DA1-5
Post boxes were also being sealed in DA 1-5, but are now being unblocked.
- Maidstone: ME
Special Delivery items were suspended in DA or ME postcodes but will resume on Tuesday.
Staff at Scotland's largest mail distribution centre at Wishaw, Lanarkshire briefly walked out on Wednesday but returned to work
later. Royal Mail said customers should continue to post letters as normal.
About 80 staff walked out of a Stoke-on-Trent mail delivery depot on Friday. Royal Mail said the ST6 post code area was worst hit.
Staff at the Cambridge sorting office walked out on Friday afternoon.
Mail centres unaffected by the action include:
Gatwick Mail Centre, Crawley
Guildford Mail Centre,
Woodbridge Meadows, Guildford
Hemel Hempstead Mail Centre, Park lane, Hemel Hempstead
Peterborough Mail Centre, Papyrus Road, Peterborough
- Reading Mail Centre,
80 Caversham Road, Reading
Royal Mail Canterbury,
Military Road, Canterbury
Mail Centre, 20 Vale Rise, Tonbridge
Southampton Mail Centre, Mitchell Way, Southampton International Airport, Southampton.
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