GESU → Textainer · lessor prefix
GESU Container Prefix — Textainer (Leasing)
Textainer, a Bermuda-based lessor managing about four million TEU, became part of Stonepeak in 2024 and absorbed the Seaco fleet at the end of 2025.
Its register footprint is the widest of any lessor — seven codes including two inherited from Seaco — which makes Textainer prefixes the ones most often misread as carrier codes.
GESU is the other ex-Seaco registration re-homed to Textainer after the 2025 acquisition.
4 letters + 7 digits, printed on the doors
GESU check digit: worked example
G | E | S | U | 5 | 7 | 5 | 7 | 3 | 4 |
|---|---|---|---|---|---|---|---|---|---|
| 17 | 15 | 30 | 32 | 5 | 7 | 5 | 7 | 3 | 4 |
| ×1 | ×2 | ×4 | ×8 | ×16 | ×32 | ×64 | ×128 | ×256 | ×512 |
| 17 | 30 | 120 | 256 | 80 | 224 | 320 | 896 | 768 | 2048 |
Sum 4759 → 4759 mod 11 = 7 → check digit 7 → GESU 575734-7
Textainer prefix family
Owner vs operator: the Textainer case
Whatever Textainer code is on the door, the tracking answer lives with the line on your paperwork — Textainer only owns the asset.
Frequently asked questions
Who owns the GESU container prefix?
GESU is registered to Textainer, a container leasing company (lessor) — the BIC register lists it together with TGHU, TEXU, TEMU, but the boxes sail in other lines' fleets.
Which line do I track a GESU container with?
Not with Textainer — a GESU 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 GESU number there.
Is GESU 5757347 a valid container number?
Yes — GESU 575734-7 passes ISO 6346 validation: the weighted letter-and-digit sum for GESU575734 leaves remainder 7 mod 11, giving check digit 7. The worked table for this GESU example is on this page.
Is GESU a shipping line prefix or a leasing company prefix?
GESU is a leasing-company (lessor) prefix — Textainer owns the steel box, while a shipping line operates it, which is why owner and tracker differ.