Leaving from YOW: uses the 100 ml / 3.4 oz rule. For return / onward travel via LHR: allows liquids up to 2 L.
Rules differ at each airport and at the destination border — read the breakdown below.
Ottawa Macdonald-Cartier (YOW) uses the 100 ml / 3.4 oz rule.
- Max container
- 100ml
- Clear bag
- Required
- Remove from bag
- Required
- Confidence
- high
CATSA 100 ml rule applies.
London Heathrow (LHR) allows liquids up to 2 L.
- Max container
- 2L
- Clear bag
- Not required
- Remove from bag
- Not required
- Confidence
- high
CT scanners rolled out across all terminals — liquids up to 2 L now permitted in cabin. Rules can revert; confirm before flying.
London has upgraded scanners — liquids up to 2 L are currently permitted in cabin. Rules can revert; confirm before flying back.
One airport allows larger containers and the other doesn't. If you need the liquid for return or onward travel, use 100 ml containers.
- Duty-free liquids in sealed STEB bags with the receipt.
- Essential medicines — declare at security.
- Baby food and baby milk for travelling infants.
- Special dietary needs may be considered case-by-case.
Email me this trip's liquid rules
Get a copy of your airport liquid rules and packing recommendation before you fly.
LiquidLimits.com is a travel planning tool, not an official airport or government source. Rules can change between trips and between terminals. Always check the official airport or aviation security guidance before you travel, and when in doubt pack to the stricter 100ml cabin-bag rule.