Horizon labels of UK

A cover from UK with a Horizon label ! 

A Horizon label is an adhesive postage label that is a type of variable value stamp. The labels were introduced in the United Kingdom in 2002 as part of the computerisation of the counter services of the post office network of Royal Mail using the Horizon System.

The first labels were large plain labels composed purely of text but later labels are of a gold colour with a Machin head and a repeating pattern of the words ROYALMAIL in order to prevent forgery.

• 14 February 2002 - First labels used in about 1000 post offices. Plain white with straight edges.
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• 30 April 2002 - Security slits added to prevent reuse.
• August & September 2002 - Labels rolled out nationally.
• April 2009 - Labels with simulated perforations appear.
• 8 June 2009 - First gold labels appear featuring the Machin head for Special Delivery only from the Camden High StreetP.O., London. Gold labels gradually introduced nationally.
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• 20 April 2010 - First labels with dual English-Welsh language inscriptions available from Welsh post offices.
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• 23 August 2010 - Straight-edged labels reintroduced first at Old Street then nationally.
• 29 September 2011 - Value Added Tax codes added.
• May 2015 - "Pre-cancelled" labels trialled at the Europhilex exhibition with corner "Single Use Only" wording. Colour changed back to white. Subsequently used nationally
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• September 2015 - Barcode added to the design.

The labels received a frosty reception from philatelists initially as they were seen as replacing postage stamps, but as they have become more complex and more stamp-like, collectors have warmed to them and they have now become a popular collecting specialism in the U.K. and an established part of modern British postal history.

The Service Indicators / tariff codes include :-

2L	2nd Class Letter
1L	1st Class Letter
1st	Letters for the Blind - to 100grams
2LG (2LL)	2nd Class Large Letter
1LG (1LL)	1st Class Large Letter
2PK	2nd Class Packet
1PK	1st Class Packet
BL	BFPO 1st Class Letter
BLG (BLL)	BFPO Large Letter
BPK	BFPO Packet
BF	BFPO Parcels
FF	Forces Freepost
FP	Fully Paid
PE	Parcel Economy International
PS	Parcel Standard International
RSF	Recorded Signed for
SD	Special Delivery
SP	Standard Parcel
A	Airmail
AAX (AX)	Airsure
SU	Surface Mail

The one used on this cover must be the Europhilex version - with the corner “ single use only” wording. The covers could make an interesting collection on modern postal history ! 

For more information - http://deltastamps.com/Fact10.htm

Update - 19-01-19

Another cover with Horizon label - marked

 A - international standard 

And also L in the corner 

With a Q code image on the label ! 

Update : 13-04-2019

A horizon label with 

IS - International Standard

And S on the corner 

With a Q code image on the label !