BSIU → Blue Sky Intermodal · lessor prefix
BSIU Container Prefix — Blue Sky Intermodal (Leasing)
Blue Sky Intermodal is a UK-managed lessor with a compact fleet placed mainly with Asian and European regional carriers.
Its single code appears rarely enough that shippers often meet it for the first time on a lease query.
4 letters + 7 digits, printed on the doors
BSIU check digit: worked example
B | S | I | U | 5 | 0 | 5 | 9 | 2 | 3 |
|---|---|---|---|---|---|---|---|---|---|
| 12 | 30 | 19 | 32 | 5 | 0 | 5 | 9 | 2 | 3 |
| ×1 | ×2 | ×4 | ×8 | ×16 | ×32 | ×64 | ×128 | ×256 | ×512 |
| 12 | 60 | 76 | 256 | 80 | 0 | 320 | 1152 | 512 | 1536 |
Sum 4004 → 4004 mod 11 = 0 → check digit 0 → BSIU 505923-0
Blue Sky Intermodal prefix family
| Prefix | BSIU (this page) |
|---|
Prefix register verified against two independent sources on 2026-08-03.
Owner vs operator: the Blue Sky Intermodal case
Blue Sky owns the steel; whichever line hired it holds the tracking record.
Frequently asked questions
Who owns the BSIU container prefix?
BSIU is registered to Blue Sky Intermodal, a container leasing company (lessor) — the BIC register lists it, but the boxes sail in other lines' fleets.
Which line do I track a BSIU container with?
Not with Blue Sky Intermodal — a BSIU box is leased, so the tracking data lives with the shipping line named on your booking confirmation or bill of lading; open that line's tracker and paste the BSIU number there.
Is BSIU 5059230 a valid container number?
Yes — BSIU 505923-0 passes ISO 6346 validation: the weighted letter-and-digit sum for BSIU505923 leaves remainder 0 mod 11, giving check digit 0. The worked table for this BSIU example is on this page.
Is BSIU a shipping line prefix or a leasing company prefix?
BSIU is a leasing-company (lessor) prefix — Blue Sky Intermodal owns the steel box, while a shipping line operates it, which is why owner and tracker differ.