In message , Peter Masson
writes
There is also a good practical reason for including the unnecessary
county in a postal address. Letters addressed to
CHISLEHURST
BR7 5xx
have not infrequently arrived late with a spurious Bristol postmark.
This does't seem to happen when they are addressed
CHISLEHURST Kent
BR7 5xx

There are also cases where two post towns in different parts of the
country share a name (Ashford, Richmond, etc). While the correct
postcode does differentiate, inclusion of the county name does reduce
the risk of misrouting.

Bearing in mind that the routing is done electronically by 'outbound
postcode' only, ie. the first portion, BR7 in your example, I fail to
see how adding the county can have any effect on this at all as it's not
even read by the system.

I've been involved with a cleansing exercise to Royal Mail preferred for
an organisation I'm involved with (which mainly involved removal of
counties) and have yet to be made aware of any problems with mail
routing in the past 2 years.
--
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