You can bring deodorant on a plane, but the allowed size depends on the type and whether it is in your carry-on or checked luggage:

• Spray, gel, cream, roll-on, and liquid deodorants: These are considered liquids or aerosols and must comply with the TSA 3-1-1 rule for carry-ons. This means each container must be 3.4 ounces (100 milliliters) or less and fit within a single quart-sized clear plastic bag along with your other liquids and gels

• Solid stick deodorants: These are not subject to the liquid restrictions and can be brought in any size in either carry-on or checked baggage without limitation

• Checked baggage: There is no size limit for deodorants in checked bags, so you can pack full-size spray, gel, roll-on, or liquid deodorants without issues. However, aerosol containers must have caps to prevent accidental discharge and must comply with airline and FAA regulations, typically not exceeding 17 fluid ounces (500 ml)

In summary:

Deodorant Type| Carry-On Size Limit| Checked Baggage Size Limit
---|---|---
Spray/Aerosol| ≤ 3.4 oz (100 ml), in quart bag| No size limit, must have cap
Gel/Cream/Liquid/Roll-On| ≤ 3.4 oz (100 ml), in quart bag| No size limit
Solid Stick| No size limit| No size limit

For convenience, many brands offer travel-sized deodorants that comply with carry-on rules. If you need larger sizes or have special medical needs, consider checking your bag or carrying documentation for medical sprays

. Always check the latest TSA guidelines before traveling to avoid surprises at security checkpoints.