Claim: On June 26, 1964, Swiss Post introduced postal codes with four digits as the third country after Germany (1941) and the United States (1963).
Evidence: Swiss Post (French: La Poste suisse, Italian: La Posta Svizzera, German: Die Schweizerische Post, Romansh: La Posta Svizra) is the national postal service of Switzerland. On 26 June 1964, Swiss Post introduced postal codes as the third country after Germany (1941) and the United States (1963). In Switzerland, the postal codes have four digits.