Likely on retention
DVSA checkJune 2026
DVSA has no vehicle assigned to this mark — most likely held on a retention certificate.
SIW 421 plate research
SIW 421
- Format
- Northern Irish
- Authority Issuer
- Londonderry
- Era
- 2017
- Status
- In Private Ownership
Price History
PWPlateworth
Current estimate
£690
EstimateDVDVLA
February 2017
£220
Sale| Source | Date | Price | Type |
|---|---|---|---|
| PWPlateworth | Current estimate | £690 | Estimate |
| DVDVLA | February 2017 | £220 | Sale |
Plateworth estimate
single price point
February 2017
1 source
84 same-format sales
estimate vs cohort
Plate History
SIW 421 is a Northern Irish registration. Plateworth's current estimate is £690 with a working range of £550 to £921, based on 1 comparable sale. The latest evidence is a sale from DVLA at £220. No active dealer listing is shown, so the page separates the Plateworth estimate from public sale evidence. This page currently shows 2 timeline events from the loaded registration record.
DVLA sale recorded
Date precision: dayFebruary 2017
Public sale record used by the valuation context.
£220
About SIW 421
Dateless registrations avoid an obvious vehicle age marker, which can make short combinations more flexible across prestige vehicles and long-term private ownership. The IW index mark traces back to Londonderry. At 6 characters, SIW 421 is a standard-length registration for this era.
DatelessLondonderryAge-neutralStandard length
Plate Speak
SIWARI
Most likely reading: "SIWARI"
Other possible readings
SIW 421SIWARISIW421Initials
Price Guide for this Format
84 same-format sold records across 71 plates currently loaded.
£100
Lowest
£1,258
Average
£8,101
Highest
Distribution
<£3k89%
£3k-£10k11%
£10k-£50k0%
£50k-£100k0%
£100k-£250k0%
£250k-£500k0%
£500k+0%