1. Why e-Passport Gates Dislike Teeth & Wide Smiles
Modern automated border control e-Gates (ICAO 9303) measure precise distances between your pupils, nostrils, mouth corners, and chin contour. A wide smile showing teeth raises the cheeks, narrows the eyes, and changes mouth-to-chin geometry enough to lower automated facial matching confidence.
2. Country-by-Country Smile Rules
While all countries ban open-mouth smiles showing teeth, there is a subtle difference regarding a soft closed-lip expression:
- United States: Allows a neutral expression or a natural, unexaggerated closed-mouth smile with both eyes open.
- United Kingdom, Canada, Australia & EU Schengen: Require a strict neutral expression—mouth closed, lips relaxed, no smiling and no frowning.
- Children under 6 (UK/Canada) & Infants (US): Exempt from strict neutral expression requirements.