TSA vs CATSA carry-on rules in 2026: checkpoint limits, 3D scanners, and fees
Verified 2026 TSA & CATSA carry-on rules: 3-1-1 liquids, 3D CT scanners, $45 ConfirmID, 100 Wh batteries, and key cross-border checkpoint differences.
Direct Answer: Key 2026 Rules
TSA and CATSA both enforce the 100 ml (3.4 oz) liquids rule and strictly ban spare lithium batteries from checked baggage. Major differences: CATSA allows domestic cannabis up to 30g (prohibited on all US flights), while TSA enforces REAL ID with a $45 ConfirmID verification protocol for non-compliant travelers.
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Quick Verdict: The 2026 TSA vs CATSA Regulatory Baseline
While the United States (TSA) and Canada (CATSA) share reciprocal aviation security agreements, critical regulatory divergences affect baggage divestiture, identification requirements, and border crossing protocols in 2026. Both agencies strictly enforce the 100 ml (3.4 oz) liquid volume cap and ban spare lithium batteries in checked holds, but US REAL ID enforcement and the TSA ConfirmID protocol introduce new compliance requirements for domestic and transborder travelers.
TSA vs CATSA Checkpoint Comparison Matrix (2026)
| Regulatory Area | TSA (United States) | CATSA (Canada) |
|---|---|---|
| Liquids Container Limit | 3.4 oz (100 ml) max per bottle | 100 ml (3.4 oz) max per bottle |
| Clear Bag Standard | 1 quart (approx. 0.95 L) | 1 liter clear resealable bag |
| Spare Lithium Batteries | ≤ 100 Wh cabin; hold banned | ≤ 100 Wh cabin; hold banned |
| ID Requirements (Domestic) | REAL ID or Passport ($45 fee without) | Govt photo ID or 2 non-photo IDs |
| Domestic Cannabis | Prohibited federally (>0.3% THC) | Permitted up to 30g (domestic only) |
| Small Scissors | ≤ 4 inches from pivot point | ≤ 6 cm (2.36 in) from pivot point |
3-1-1 Liquids Rule: Status Across US and Canadian Hubs
The 3-1-1 liquids rule remains in full effect at all US commercial airports. Regardless of whether an airport utilizes next-generation Smiths Detection or Analogic 3D computed tomography (CT) scanners, passengers cannot bring containers larger than 100 ml (3.4 oz), even if partially full. In Canada, CATSA enforces the identical 100 ml container ceiling, but exemptions apply universally to medically necessary liquids, baby formula, and breast milk in reasonable quantities.
3D CT Scanners & Baggage Divestiture Changes
Computed Tomography checkpoint lanes allow security algorithms to render full 3D volumetric images of carry-on bags. At equipped lanes, travelers are instructed to leave laptops, tablets, and 3-1-1 liquid bags inside their luggage. However, standard lanes operating legacy 2D X-ray systems still require complete bin divestiture. Passengers should pack electronics and liquids at the top of their carry-on to accommodate whichever lane configuration is assigned.
Lithium Battery & Power Bank Limits
FAA (49 CFR § 175.10) and Transport Canada regulations strictly mandate that all spare lithium-ion batteries and power banks remain in the aircraft cabin. The standard consumer threshold is 100 watt-hours (Wh), which equates to roughly 27,000 mAh at 3.7 volts. Batteries between 101 and 160 Wh require airline approval and are capped at two spares per passenger. Batteries exceeding 160 Wh are completely forbidden on passenger flights.
REAL ID Enforcement and the TSA ConfirmID Protocol
Full enforcement of the REAL ID Act is active across all US airport checkpoints. Domestic travelers must present a REAL ID-compliant state driver’s license (marked with a star), a US passport, DHS trusted traveler card (Global Entry, NEXUS, SENTRI), or military ID. Under the TSA ConfirmID protocol enacted in early 2026, passengers lacking compliant ID may undergo alternate identity verification for a $45 administrative fee, valid for 10 calendar days.
US Preclearance at Canadian International Airports
Eight Canadian airports (Calgary, Edmonton, Halifax, Montreal, Ottawa, Toronto Pearson, Vancouver, and Winnipeg) feature US Customs and Border Protection (CBP) Preclearance facilities. When flying from these hubs to the US, passengers clear US customs and TSA-equivalent security inspection before boarding. Once landed in the United States, flights arrive as domestic services with no secondary customs screening.
Frequently Asked Questions
What is the main difference between TSA and CATSA carry-on liquids rules?
Both TSA and CATSA enforce the 100 ml (3.4 oz) per container limit in one clear 1-liter (quart) resealable bag. The critical difference is in divestiture: at Canadian CATSA lanes with CT scanners, liquids almost always stay in bags, whereas in the US, lane equipment varies widely across 430+ commercial airports.
Does Canada allow more battery capacity than the US?
No. Both CATSA (under Transport Canada TDG Regulations) and TSA (under FAA 49 CFR § 175.10) set 100 watt-hours (Wh) as the unrestricted cabin threshold. Batteries rated between 101 and 160 Wh require airline approval (maximum 2 spares), and all standalone lithium batteries remain banned in checked baggage.
What is the TSA ConfirmID rule starting in 2026?
Effective February 1, 2026, TSA charges a mandatory $45 identity verification fee for travelers without REAL ID-compliant identification or a valid passport at US airport checkpoints, granting a temporary 10-day domestic clearance window.
Are duty-free liquids from Canada allowed on connecting US flights?
Only if purchased inside a preclearance secure zone or packed inside an intact Secure Tamper-Evident Bag (STEB) with a receipt dated within 48 hours. If entering the US and clearing customs before a domestic connection, large liquids must go into checked luggage.
Can I bring cannabis through CATSA security on domestic Canadian flights?
Yes. Under Canadian federal law, passengers of legal age (18 or 19 depending on province) may carry up to 30 grams of dried cannabis on domestic flights within Canada. However, crossing the international border into the US with any cannabis remains a federal felony.