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Saturday at the lake, three people in the boat and one in the water. Before the first pull, the driver runs through it out loud: vest buckled, who’s watching, the flag is in the holder, and “thumbs up means faster, hand on the head means we’re done.” The observer turns to face the skier, and only then does anyone say “Hit it.” This page covers the water skiing rules that matter most: who must be in the boat, observer, flag, hours and life jacket laws, hand signals, safe driving and pickups, and how competitions are scored.
Boating laws differ by state and sometimes by lake. This page explains the common rules in plain words; check your state’s boating agency for the exact law where you ski.
Who makes the rules
The US Coast Guard sets federal minimums (life jackets aboard, engine cut-off switches, and a ban on negligent operation, which it says can include “hazardous water skiing or other water sports practices”). The states add the towing rules: observers, flags, hours and what the skier wears. Competitions follow the rule books of USA Water Ski & Wake Sports and the International Waterski & Wakeboard Federation (IWWF).
The team: skier, driver and observer
Water skiing is a three-person sport. The driver watches where the boat is going, the observer watches the skier, and the skier signals what they need. California’s boating guide notes that many accidents happen because the driver was watching the skier and missed a hazard ahead. States require the observer:
- California: at least two people aboard a boat towing a skier, the operator and an observer 12 years of age or older.
- Oregon: another person besides the operator who is in a position to continuously observe the person being towed (competitive events may use a curved rear-view mirror instead).
- Florida: a person besides the operator “in a position to observe the progress of the person being towed,” or a wide-angle rear-view mirror.
- Pennsylvania: at least one competent observer in addition to the operator; a no-observer exception needs a special permit and a ski flag.
Even where a mirror is legal, the BoatUS Foundation advises an observer “whose only job is to watch the skier.”
The skier-down flag
A skier in the water is hard for other boats to see. Several states, mostly in the West, require a skier-down flag. Oregon’s law says the flag must be international orange or red, at least 12 by 12 inches, and held up, visible from all sides, as soon as a towed person is down in the water. California makes a ski flag mandatory to show a skier, a ski or a line in the water, and Missouri requires a red or orange flag on its main rivers and lakes during set daytime hours whenever a person is in the water before or after being towed. California’s guide also tells a fallen skier to hold a ski up vertically to warn approaching boats.
Hours and life jacket rules
- Daylight only: California and Pennsylvania prohibit towing sports between sunset and sunrise; Florida bans water skiing from half an hour after sunset to half an hour before sunrise.
- A life jacket on the skier: Florida requires a noninflatable, Coast Guard-approved life jacket worn by the person being towed, and Pennsylvania requires a Coast Guard-approved wearable life jacket and prohibits inflatables.
- The wetsuit exception: California requires a Coast Guard-approved Type I, II, III or V life jacket on anyone being towed, but a skier on a marked slalom course, or a barefoot, jump or trick skier, may wear a wetsuit labeled by its maker as a water ski wetsuit instead, as long as a life jacket for that skier is carried on board.
- No ski belts, no inflatables: California’s guide notes that ski belts are not Coast Guard approved, and that inflatable life jackets are not approved for water skiing. The Coast Guard warns that some approved jackets are labeled not approved for water skiing, so read the label.
Neoprene vests approved for towed sports are the standard: the O’Brien Traditional Neoprene (about $85) is approved in the US and Canada, and the O’Neill SuperLite (about $50) is a Type III vest the maker labels for wake, ski and tubing. Our water skiing gear page compares more.
Hand signals every skier and observer should know
A boat is loud, so skiers talk with their hands. These are the standard signals taught by the BoatUS Foundation and shown, as approved by USA Water Ski, in California’s guide:
| Signal | Meaning |
|---|---|
| Shout “Hit it” or “OK,” or nod | Ready: start pulling |
| Thumb up (or palm up) | Faster |
| Thumb down (or palm down) | Slower |
| “OK” sign (thumb and finger in a circle) | Speed is good, or signal understood |
| Arm out, pointing left or right | Turn that way |
| Hand raised, palm forward | Stop |
| Slashing motion across the neck | Cut the motor |
| Pat on the top of the head | Back to the dock |
| Hands clasped over the head (after a fall) | I’m OK |
| Ski held straight up out of the water | Pick me up / skier down, watch out |
After every fall, the skier gives “I’m OK” right away; if the observer doesn’t see it, they tell the driver at once.
Driving rules: the pull, the turns and the pickup
- Check the rope first. California’s guide warns that a towline “can cut like a knife.” Before pulling, make sure the rope isn’t caught in the propeller or wrapped around the skier, and don’t accelerate until the skier holds the handle, has the skis in position and signals ready.
- A smooth pull and the right speed. Ease the throttle until the skier is up, then match the speed to the skier; the same guide suggests 18–25 mph for beginners, depending on weight and ski size.
- No sharp turns, especially while the skier is cutting outside the wake. If you must turn suddenly, throttle back and signal the turn.
- Go back right away after a fall, approach slowly from the driver’s side so the skier stays in view, never back the boat up to a person in the water, and shut off the engine as you come near. A propeller can still turn with the engine idling in neutral.
- Engine off for boarding. The BoatUS Foundation says never leave the boat running while a skier climbs back aboard, and never use the engine or propeller as a step.
- Wear the engine cut-off switch lanyard. Federal law requires operators of boats under 26 feet to use an installed cut-off switch when on plane or above displacement speed.
Propellers and carbon monoxide
In the Coast Guard’s 2024 statistics there were 169 incidents in which someone was struck by a propeller, causing 30 deaths and 158 injuries. The Coast Guard says most involve open motorboats 16 to 25 feet long and operator inattention. Keep people off the swim platform with the engine on, and never “teak surf” (hanging on the platform to ride the wake), which the Coast Guard calls “NEVER a safe activity.” Carbon monoxide poisoning looks like seasickness: irritated eyes, headache, nausea, weakness or dizziness. Move the person to fresh air and get medical help.
Competition rules
Slalom: buoys, speeds and rope lengths
The skier rounds six buoys in a zigzag course. Everyone starts on a 75-foot rope at their division’s starting speed; the boat speeds up each pass until the division’s top speed (36 mph for men and 34 mph for women in the open divisions), and then the rope is shortened in set steps until the skier misses a buoy or falls. A full buoy means rounding it and getting back to the wake; half and quarter buoys count partial credit. The score is the buoys rounded at the shortest rope reached. The rope steps have names:
| Called | Rope length |
|---|---|
| Long line | 75 ft (23 m) |
| 15 off | 60 ft (18.25 m) |
| 22 off | 53 ft (16 m) |
| 28 off | 47 ft (14.25 m) |
| 32 off | 43 ft (13 m) |
| 35 off | 40 ft (12 m) |
| 38 off | 37 ft (11.25 m) |
| 39.5 off | 35.5 ft (10.75 m) |
| 41 off and 43 off | The world-record zone |
Tricks and jump
- Tricks: two 20-second passes. Each trick has a point value and counts only once. Skiers choose their speed, around 18–20 mph, and judges score the run.
- Jump: three attempts off a ramp, distance only, no style points. The standard ramp is 5 feet; elite women jump off 5.5 feet and elite men off 6 feet. Helmets are mandatory in the jump event.
- Overall: scores from all three events are combined with a special formula for an overall result.
Boats and drivers in tournaments
Fair slalom needs the same pull for every skier, so USA Water Ski approves specific tournament towboats and requires a GPS speed control system (Zero Off) on boats at the bigger events. Drivers are rated too: a USA Water Ski Trained Boat Driver must be at least 16 and pass a record check, an online course and exam and an on-water evaluation before driving grassroots tournaments, clinics and club practices; show ski practices need drivers rated by the National Show Ski Association.
Show skiing and barefoot
Show ski teams are judged on their acts (swivel skiing, doubles, freestyle jumping, pyramids) for execution and presentation. Barefoot has three events of its own: slalom (points for crossing the wakes), tricks (two 15-second passes, each trick once) and jump off a ramp only 18 inches high, at more than 60 km/h.
Gear that helps you follow the rules
After the vests, add a flag and the right rope. The Seachoice vinyl water ski flag (about $16) is a 12-by-12-inch marine orange flag on a 24-inch pole that the maker says conforms to the laws of Arizona, California, Colorado, Missouri, Texas, Washington and other states. For the rope, the BoatUS Foundation suggests a towline at least 75 feet long; the Proline handle and 75-foot, 8-section rope (about $110) has a floating 3/8-inch line you can shorten section by section as a slalom skier improves.
Seachoice Vinyl Water Ski Flag
- 12 x 12 in marine orange
- 24 in PVC pole
- Maker: conforms to AZ, CA, CO, MO, TX, WA and other state laws
Proline Waterski Handle and 75' 8-Section Rope
- 75 ft, 8 sections
- 12 in rubber handle
- Floating handle and mainline
O'Brien Traditional Neoprene Life Jacket
- US Coast Guard and Transport Canada approved
- Neoprene
- Adjustable straps and buckles
O'Neill SuperLite USCG Life Vest
- USCG Type III
- Four quick-release buckles
- Sizes S to 4XL
Back to the water skiing hub, or see youth water skiing, leagues and associations, injuries and gear. Wakeboarding and wakesurfing have their own rules page: /sports/wakeboarding/rules/.
Water skiing rules questions
How old does a water ski observer have to be?
It depends on the state. California requires an observer at least 12 years old; other states, such as Pennsylvania, ask for a “competent” observer. Choose someone who will watch the skier the whole time and knows the signals.
Do I need a skier-down flag?
In some states, yes. Oregon and California require one, Missouri requires one on its main rivers and lakes during set hours, and the rule is most common in western states. A flag at least 12 by 12 inches, orange or red, held up whenever a skier or gear is in the water meets the strictest rules.
Can I wear an inflatable life jacket for water skiing?
No. Florida, Pennsylvania and California rules don’t allow inflatables for towed skiers, and some approved jackets are labeled not approved for water skiing. Wear a foam or neoprene vest approved for towed sports.
What does a hand on the head mean in water skiing?
Patting the top of your head means “take me back to the dock.” Hands clasped over the head after a fall means “I’m OK.”
How is a slalom water ski course scored?
By buoys rounded. The skier runs six buoys while the boat speeds up to the division’s top speed, then the rope is shortened after each clean pass. The score is the buoys rounded at the shortest rope reached, such as “3 at 32 off.”