Can you cross the Canada-US border with cannabis if it is legal on both sides?

No. Crossing the international border with cannabis is a federal offence in both directions regardless of provincial or state legality, and it applies to medical product too. Leave all of it behind, including the vape pen at the bottom of the bag.

Do children need a passport to cross the border by car?

Children need their own travel document, and a passport is the simplest. If a child is travelling without one or both parents, carry a signed consent letter from the absent parents; officers ask for it regularly enough that it belongs in the glovebox.

Is NEXUS worth getting?

If you cross by land more than a couple of times a year, yes. It gives dedicated lanes at major crossings in both directions plus trusted-traveller screening at airports, and the membership runs five years. The bottleneck is scheduling the enrolment interview.

Getting around

Crossing the Canada-US border by car, without the drama

Documents for adults, kids and pets, what never crosses in either direction, and how NEXUS and the wait-time pages change the trip.

3 min read 3 sections 3 questions answered

The land border is the easiest international crossing most travellers will ever make, and still manages to generate the most pre-trip anxiety. The formula is short: right documents, honest answers, nothing in the cooler you would have to think twice about. Everything else is queue management.

The white Peace Arch monument on the grass border between Blaine, Washington and Surrey, BC — The Peace Arch between BC and Washington, the border at its most ceremonial. Photo: Vmenkov, derivative work Myrabella / Wikimedia Commons, CC BY-SA 3.0

Documents

Adults: a passport is the clean answer. A NEXUS card works at the land border in both directions; an enhanced driver's licence from a province or state that issues them also works for its holders.
Kids: their own passport, plus a consent letter if a parent or guardian is not on the trip. Border officers ask about it more than people expect.
Pets: proof of rabies vaccination for dogs and cats. Rules firmed up on the US side in recent years, so check the current CDC dog requirements before a trip with a dog.
Rental cars cross fine in both directions in almost all cases, but carry the rental agreement and confirm cross-border use is authorized on it.

What never crosses

Cannabis, in either direction, full stop. Legal in Canada and in many states, and still a serious federal offence to carry across; this is the single most consequential mistake available at this border.
Firewood. Moving it spreads invasive insects and both countries restrict it; buy where you burn.
Most fresh produce, and many meats and plants, depending on direction and origin. When in doubt, eat it before the booth or declare it and let the officer decide.
Undeclared anything. Duty owed is a small bill; a false declaration is a seized cooler and a flag on your file. Declare cheerfully and completely.

Allowances and the queue

Alcohol and tobacco exemptions depend on direction and how long you were away, and the amounts get amended, so check the official pages rather than a forum memory: CBSA's I Declare for returning to Canada, CBP's Know Before You Go for entering the US. For the queue itself, both agencies publish live wait times per crossing, and the pattern is stable: mid-week mornings are quick, holiday Sunday afternoons are not, and the small crossing twenty minutes off your route is often an hour faster than the famous one on it. Frequent crossers should do the NEXUS interview once and use the dedicated lanes forever after.

The official pages

Common questions

Can you cross the Canada-US border with cannabis if it is legal on both sides?: No. Crossing the international border with cannabis is a federal offence in both directions regardless of provincial or state legality, and it applies to medical product too. Leave all of it behind, including the vape pen at the bottom of the bag.
Do children need a passport to cross the border by car?: Children need their own travel document, and a passport is the simplest. If a child is travelling without one or both parents, carry a signed consent letter from the absent parents; officers ask for it regularly enough that it belongs in the glovebox.
Is NEXUS worth getting?: If you cross by land more than a couple of times a year, yes. It gives dedicated lanes at major crossings in both directions plus trusted-traveller screening at airports, and the membership runs five years. The bottleneck is scheduling the enrolment interview.

Tip

Keep the documents in one envelope in the glovebox: passports, consent letter, pet papers, rental agreement. The crossing where you need a document is never the crossing where you feel like unpacking a suitcase to find it.