Put the zip code first

Original Article ↗ Hacker News Discussion ↗

Core proposal: ZIP/postcode first

  • Many agree the basic idea—using a high‑information field early to auto-fill city/state/country—can reduce typing and feel snappier.
  • Several note this is already common in some countries (e.g., UK, NL, IE, JP) where postcodes are fine-grained and backed by good postal databases.
  • Some suggest a refined pattern: country first (possibly prefilled via IP), then postal code, then the rest.

Limitations of ZIP codes (even in the US)

  • Multiple comments stress: ZIPs are about delivery routes, not political boundaries.
  • ZIPs can:
    • Map to multiple cities and even multiple states.
    • Change over time.
    • Cover PO boxes only or unusual entities (boats, large campuses).
  • USPS treats each ZIP as having a “preferred” city and alternates; mail works even with “wrong” city, but legal/municipal boundaries often differ.

International & format issues

  • Many point out that:
    • “ZIP code” is US‑specific; other countries use postal codes with different formats (length, letters, digits, or none at all).
    • Numeric-only inputs and 5‑digit assumptions break for Canada, much of Europe, etc.
    • The claim that 5 digits determine the country is flatly rejected; the same codes exist in multiple countries.
  • Non‑US readers often see US‑centric design as actively hostile or unusable.

UX, autofill, and validation

  • Several argue built‑in browser autofill is simpler and often superior: no typing at all if forms are standard.
  • Over‑eager validation and “corrections” frequently reject valid foreign addresses or diacritics, causing drop‑offs.
  • Auto-fill should be suggestion, not hard validation; users must be able to override guessed city/state.

Data & implementation complexity

  • Maintaining accurate global postcode→place mappings is non‑trivial; commercial datasets are incomplete, expensive, and change.
  • For US‑only or single‑country sites, ZIP/postcode‑first can work well if backed by postal data and still editable.

Alternative approaches

  • Some favor:
    • Country → postcode → structured fields (with soft autocomplete).
    • Or even a single free‑text, multi‑line address box parsed server‑side.
  • Others note address entry isn’t a huge burden; “clever” flows often fail more than they help.

Tone and reception

  • Many criticize the original site’s US‑centric framing and later snarky geo‑targeted messages as condescending.
  • Nonetheless, several commenters see merit in the underlying principle if adapted carefully and globally.