Bangladesh (BD) — licensing trace

Checked 2026-08-29. Starting from zero — no prior work anywhere for this country code.

Postal system

Bangladesh uses a 4-digit numeric postal code system administered by Bangladesh Post Office.

Source checked — GeoNames BD

https://download.geonames.org/export/zip/BD.zip   # 1,349 rows

No per-country caveat for Bangladesh in GeoNames' export/zip/readme.txt — the general CC BY 4.0 licence applies without restriction.

Verified directly against the raw file: 1,349 rows, all 1,349 distinct postal codes (no duplicates on the code itself). Unlike South Africa's postal export, this one already carries three real admin tiers on every single row: admin_name1 (Division, e.g. "Dhaka Division"), admin_name2 (District, e.g. "Dhaka"), and admin_name3 (Thana/Upazila, e.g. "Paltan") — 100% populated on all three, no join or enrichment needed.

Official source — checked, no bulk export found

Bangladesh Post Office's own site (bangladeshpost.gov.bd) was checked via search; no bulk postal-code download, API, or open-data catalogue entry was found. Bangladesh Bureau of Statistics was also checked — no postal-code dataset located (BBS publishes census/administrative geography, not postal codes).

Third-party alternatives — checked, none better than GeoNames

Search surfaced several community mirrors (postalbin.com, bgd.postcodebase.com) and PDF scans of the printed postal directory (Scribd uploads of the official directory, government district-portal PDFs). None offers a machine-readable bulk file with a stated open licence — they are either copies of the same printed directory with no licence grant, or read-only lookup sites. None was pursued further given GeoNames already provides equal or better structured coverage under a clean, unambiguous licence.

Decision

{
  "channel": "postal-codes-r2",
  "source_url": "https://download.geonames.org/export/zip/BD.zip",
  "licence_id": "CC-BY-4.0",
  "collected_at": "2026-08-29",
  "decision": "compatible",
  "decided_by": "claude-session-2026-08-29",
  "decided_at": "2026-08-29"
}

Proposed tier

B ($49). Single source normalised in place — real work (ISO 3166-2:BD crosswalk for admin_code1, cleaning GeoNames' internal admin1/admin2 codes into real identifiers if any exist) but no second authoritative source to consolidate. Not A.

Verdict

Clean and strong for its size — smallest of this batch's three (1,349 rows) but the only one of the three with full three-tier admin coverage already present in the postal export itself, no gazetteer join required. Not yet built; this is the research/decision record only.

Build — 2026-08-30 (local only, not published)

Built via datasets/bd/scripts/build_postal_codes_product.py. Found and fixed a real defect not caught in the research pass: 77 rows carried admin_name1="Dhaka Division" but a DIFFERENT internal GeoNames code ("H") than the other 298 real Dhaka rows ("81") — those 77 rows' districts (Jamalpur, Mymensingh, Netrakona, Sherpur) are exactly Mymensingh Division, split from Dhaka in 2015. GeoNames' own coding already separated them correctly; only the name string was stale. Corrected to "Mymensingh Division" — result is 8/8 real divisions, 64 districts (matches Bangladesh's real district count exactly), 483 thanas, all populated on 100% of rows. admin_code1 derived to verified ISO 3166-2:BD codes (A–H, confirmed against Wikipedia).

Frictionless validation: valid: True.

Status: built and validated locally only. Nothing published to R2, nothing committed to git. datasets/bd/README.md and datapackage.yml updated in place (tier B, premium_source_key: bd/bd.zip, real sources/licenses, replacing the "Multiple sources" placeholder).