Aquatic Invasive Species Decal Requirements for Boats

Aquatic invasive species decal requirements for boats vary by state, but the pattern is consistent: if you’re launching a motorized vessel on public waters in a state that runs an AIS program, you need to buy that state’s decal, display it correctly, and follow the state’s clean, drain, and dry rules every time you leave the water. A decal from one state does not satisfy another state’s requirement, so check with the fish and wildlife agency in each state you plan to boat in before you trailer.

Which Boats Need a Decal

In states that require one, any motorized watercraft launched on public waters almost always needs a decal, whether the motor runs on gasoline, diesel, or electricity. Residency matters for the price. The state where your boat is registered determines whether you pay the resident or non-resident rate, and out-of-state visitors generally pay more.

There is no broad reciprocity between states. If you cross state lines with your boat, expect to buy a separate decal in each state that requires one.

Non-motorized craft like kayaks, canoes, and stand-up paddleboards fall under decal requirements in some states as well, at a lower fee. Small inflatables and non-motorized vessels under ten feet are exempt in several jurisdictions. If you rent from a marina, the decal is usually already on the boat. If you run a guide service, each vessel in your fleet needs its own valid decal for every state you operate in, and some states add permit requirements on top for commercial watercraft transporters.¹

What a Decal Costs and How to Buy One

Fees vary by state, vessel type, and residency. Resident motorized boaters typically pay somewhere between $5 and $25 per year. Non-residents launching motorized craft commonly pay $15 to $50. Non-motorized permits usually run $5 to $15. The fees are modest by design, meant to fund inspection stations and decontamination equipment rather than generate general revenue.

Online

Most state wildlife agencies sell decals through an online portal. You pay, and the system issues a temporary authorization immediately — usually valid for about 30 days while the physical sticker ships. Print the receipt and keep it aboard until the permanent decal arrives. This is the fastest option if your trip is days away.

In Person or by Mail

Authorized vendors — sporting goods stores, bait shops near popular ramps, regional wildlife offices — sell decals over the counter, so you walk out with the sticker in hand. Some states still accept a paper application with a check, but processing and delivery can take two to four weeks. If a mailed decal doesn’t arrive on time, contact the agency to confirm your payment cleared before you head to the water.

Information You’ll Need

Every application asks for your vessel’s Hull Identification Number. The HIN is a 12-character alphanumeric code that includes a manufacturer code, serial number, and date of manufacture.² You’ll find it on the starboard side of the transom, near the top.³ Beyond the HIN, expect to provide the manufacturer name, model year, vessel length, propulsion type, and your mailing address. Errors here cause processing delays that can leave you without valid proof on launch day.

Where to Put the Decal

Each state specifies exactly where the sticker goes, and the rules are not uniform. Some want it near the registration numbers on the bow. Others require a specific side of the hull. The consistent rule everywhere is that the decal must be clearly visible above the waterline so officers can verify compliance without boarding. Read the instructions that ship with your decal. Placing it in the wrong spot can draw a citation even though you paid the fee. Clean and dry the hull surface before applying it, or the adhesive will fail within a few outings.

Clean, Drain, and Dry Rules Apply Alongside the Decal

The decal is only part of compliance. Roughly 33 states enforce legally binding clean, drain, and dry obligations that apply to every trailered boat leaving public waters, whether that state charges for a decal or not.⁴

Clean

Thirty-one states require boaters to remove all visible organic material from the hull, trailer, and equipment before leaving a launch area. That means pulling off plant fragments, mud, and anything alive that hitched a ride. In 19 of those states, the requirement applies statewide to all waters. Others limit it to specific high-risk water bodies or target particular species.⁴

Drain

Twenty-seven states have drain plug laws requiring boaters to pull all drain plugs, bailers, and valves before trailering away from the water.⁴ In most of these states, plugs must stay out and open during transport on public roads. Standing water in livewells, bilges, and ballast tanks is how mussel larvae travel from lake to lake. In a drain-plug state, an officer who spots a seated plug on a trailered boat can cite you on the spot.

Dry

Eight states have explicit drying requirements written into law, though every AIS program in the country recommends it.⁴ Drying time depends on the weather. Hot summer sun may kill dreissenid mussels in a few days. Cooler conditions can push that to a week or more before the boat can safely enter a new water body.

Inspection Stations and Decontamination

Several states operate mandatory watercraft inspection stations, especially near high-value or high-risk waters. When a station is open, you are legally required to stop. Driving past an open inspection station is treated seriously. At least one state classifies it as a gross misdemeanor, and others impose escalating fines for repeat offenses.⁵

Inspectors check the hull, trailer, bilge, livewell, ballast tanks, and any compartment that could hold water or organic material. If they find something concerning, they can order a professional decontamination before you’re allowed to launch. After a professional decontamination, inspectors typically apply a tamper-evident seal to the vessel. The certification stays valid only as long as that seal is intact. Once it’s broken, tampered with, or removed, the boat is treated as uninspected and may need to go through the process again before launching somewhere new.

Penalties for Skipping Any of This

Consequences range from modest fines for a first offense to criminal charges for repeat or willful violations. Specifics depend on your state, but the pattern is consistent. First offenses draw civil fines, and the numbers climb from there. Repeat offenders can face misdemeanor charges carrying larger fines and, in some cases, jail time.⁶

Conservation officers also have authority to impound your vessel if you refuse an inspection, if decontamination cannot be performed on-site, or if a mandatory drying period needs to be enforced. When impoundment follows a refusal to cooperate, the owner is typically liable for all impoundment costs.⁷ Officers can also prevent you from launching entirely, which ends your trip before it starts. A decal costs a fraction of what any citation does, and the few minutes it takes to clean, drain, and dry your boat at the ramp costs nothing at all.

1
National Invasive Species Information Center. Aquatic Invasive Species Decals
2
eCFR. 33 CFR 181.25 – Hull Identification Number Format
3
U.S. Coast Guard. Boating Safety Circular 70
4
National Sea Grant Law Center. Inventory of State Legal Requirements to Clean, Drain, and Dry Watercraft
5
National Sea Grant Law Center. State Watercraft Inspection and Decontamination Programs
6
Mississippi-Alabama Sea Grant Legal Program. WaterLog Volume 42.2 – State Laws Versus Invasive Species
7
National Sea Grant Law Center. Model Regulation for State Watercraft Inspection and Decontamination Programs