21 SI Number Plate
The known history of 21SI, bringing together documented vehicle assignments, auction sales, advertisements, photographs and other evidence.
Last checked by our plate checker: 13 Sept 2026, 01:14
21 SI (21SI) — Number Plate History & Timeline
Also written as 21SI. History, past vehicles, DVLA records, auction sales, advert appearances, spotted photos, pictures and images for number plate 21 SI.
Issued
This number plate was originally issued between 1903 and January 1963
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What is 21 SI worth?
The value of 21 SI is influenced by its dateless format, the relevance and popularity of the letters SI and comparable sales.
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