Beach Safety & Lifeguards on Nantucket

What to know before you swim — every beach, every condition, every season.

Photo by: Michael Torrisi

The Essentials

Know Before You Go

Nantucket’s beaches range from calm harbor shorelines to exposed Atlantic surf. Conditions can change quickly depending on tides, wind, and weather, making preparation an important part of any beach day.

Visitors traveling with children, unfamiliar with local surf conditions, or exploring multiple beaches during their stay should take time to understand the differences between shoreline areas before heading out.

Swimming near staffed lifeguard beaches, checking surf conditions, and staying aware of changing tides can help create a safer and more enjoyable experience on the island.

Beach Safety Quick Tips

Never swim alone
Stay within your swimming ability
Cold water can reduce strength and endurance
Avoid diving into shallow or unfamiliar water
Swim near lifeguards whenever possible
Watch for rip currents and changing surf
If caught in a rip current, stay calm and swim parallel to shore
Avoid swimming under the influence of alcohol
Use caution when body surfing in breaking waves
Respect warning flags and posted beach advisories
Avoid swimming when seals are in proximity

Guarded Beaches

Which Nantucket Beaches Have Lifeguards?

The Town of Nantucket staffs lifeguards at ten beaches each summer. Coverage runs daily from 9 AM to 5 PM, weather permitting.

Outside these hours — and at all other island beaches — swimming is at your own risk.

Children's Beach

Children’s Beach is a calm harbor beach near downtown Nantucket with seasonal lifeguards, restrooms, a playground, and summer activities within walking distance of town.

Cisco Beach

Cisco Beach is a popular surf beach at the end of Hummock Pond Road with heavy surf, seasonal lifeguards, soft sand, parking, and strong rip currents.

Dionis Beach

Dionis Beach is a calm Nantucket Sound beach with seasonal lifeguards, shallow water, harbor views, restrooms, and strong family appeal, though access requires a walk over soft sand dunes.

Jetties Beach

Jetties Beach is a calm, family friendly beach near town with seasonal lifeguards, restrooms, dining, accessible features, water sport rentals, and wide sandy shores.

Ladies Beach

Ladies Beach is a south shore beach near Bartlett Farm known for strong surf, body surfing, boogie boarding, and access through dunes from a nearby parking area.

Madaket Beach

Madaket Beach is a popular west end beach known for sunsets, soft sand, heavy surf, limited seasonal lifeguards, and minimal facilities.

Miacomet Beach

Miacomet Beach has strong surf and rip currents with limited seasonal lifeguards, parking, and no facilities or food service.

Nobadeer Beach

A popular beach near the airport with strong surf, seasonal lifeguards, limited parking, occasional food trucks, and a wide shoreline suited for surfing, fishing, picnics, and beach games.

Sconset Beach

A wide beach at the eastern end of the island with strong surf, easy access for seniors, nearby village restaurants and restrooms, and seasonal access by shuttle or bike path.

Surfside Beach

One of Nantucket’s most popular family beaches with seasonal lifeguards, restrooms, food service, strong surf, wide sandy shores, and plenty of space for swimming, surfing, shelling, and beach games.

Safety System

Reading the Beach Flag System

Nantucket’s guarded beaches use a color-coded flag system to communicate ocean conditions at a glance. Flags are posted each morning and updated throughout the day. Always check the flags before entering the water.

If conditions change significantly mid-day, lifeguards will update the flags and make a beach announcement. When in doubt, ask the on-duty guard directly.

Flag Legend

Green
Low Hazard

Calm conditions.
Safe swimming for most visitors.

Yellow
Medium Hazard

Moderate surf or currents. Use caution. Weaker swimmers should stay close to shore.

Red
High Hazard

Strong surf or dangerous currents. Strong swimmers only. Children should stay out of the water.

Purple
Marine Life Warning

Dangerous marine life spotted near shore
jellyfish, sharks, or similar.

Double Red
Beach Closed

For Your Safety the Beach is Closed
NO Swimming in this area.

Understanding Ocean Conditions on Nantucket

Beach conditions on Nantucket vary significantly from one shoreline to another. North shore beaches are often calmer, while south shore beaches experience stronger surf and changing currents.

Ocean conditions may shift throughout the day depending on tides, offshore weather systems, and wind direction.

Rip Currents

Rip currents are the leading cause of surf accidents. These strong currents flow away from shore and can quickly pull even experienced swimmers into deeper water. They form when waves push large amounts of water toward the beach, which then rushes back out through narrow channels. Larger waves often create stronger rip currents. They may stay in one area or shift along the shoreline. Rip currents are sometimes visible as darker or sandy colored water.

Lateral/Longshore Currents

Lateral or longshore currents flow parallel to the shoreline and are generated when ocean waves approach the beach at an angle. They range in speed from fast-flowing to more subtle movement. These currents pose little threat to the average swimmer, but weaker swimmers can be pulled into rip currents and heavy surf simply by the force of lateral currents.

Undertow

Undertow usually occurs with high tides on beaches that rise sharply away from the water’s edge. Backwash occurs when the water remaining on the beach returns forcefully to the surf beneath later incoming waves. It is particularly dangerous for small children playing near the water’s edge. Even in the short distance between breaking waves and deep water, backwash is powerful enough to knock people off their feet.

Shore Break

Shore Break can occur at high tide when heavy surf conditions cause large waves to break on the beach with little or no water under them. Shore break can be particularly dangerous to a swimmer who is caught in such a wave because the wave can slam the swimmer on the beach, causing injury. Shore break is the most frequent cause of serious back, neck, and shoulder injuries at the beach. Avoid body surfing during shore break conditions.

Rules & Etiquette

Beach Rules on Nantucket

Follow Lifeguard Direction

Lifeguards have full authority on the beach. Follow their instructions at all times, without exception.

Flotation Devices

Flotation devices are permitted at the lifeguard's discretion. Guards may restrict use based on current conditions.

No Unleashed Dogs

Dogs must be leashed at all times on Nantucket beaches. Unleashed dogs are not permitted.

No Fishing

Fishing is not allowed at lifeguarded beaches during staffed hours.

No Kite Flying

Kite flying is prohibited on all Town of Nantucket lifeguarded beaches.

Beach Driving

Permitted in designated areas with an annual Town of Nantucket beach vehicle sticker. Learn more & obtain a sticker →

No Open Fires

Open fires of any kind are not permitted on lifeguarded beaches.

No Alcohol

Alcohol is prohibited on all Town of Nantucket lifeguarded beaches.

Beach Holes

Sand holes must not exceed waist depth. Fill in any hole completely before leaving the beach.

For Families

Choosing the Right Beach for Families

Not all Nantucket beaches are equal for young swimmers. Water depth, wave exposure, and proximity to amenities vary dramatically across the island’s 82 miles of shoreline.

For families with children under 10, Children’s Beach and Jetties Beach are the clear first choices. Both offer lifeguard coverage, calm harbor water, and easy access to restrooms and food.

Children’s Beach sits in the heart of Nantucket Town, making it easy to combine a beach morning with lunch nearby or a stop at the Whaling Museum. Jetties Beach adds kayak rentals, a playground, and a snack bar.

Families who prefer a more expansive beach may enjoy the south end of Surfside Beach, where lifeguards are stationed and the sand is wide and open.

Best Beaches for Young Swimmers

Children’s Beach — calmest water, most central
Jetties Beach — calm harbor water, full amenities
Surfside Beach — wide sand, guarded zone, gentle inner surf

4WD Access

Beach Driving on Nantucket

For many visitors, beach driving offers access to some of Nantucket’s most remote and scenic stretches of shoreline. Beach vehicle access is available only in designated areas and requires a valid permit issued by the Town of Nantucket. Beach driving is permitted only where indicated on the official Beach Driving Map and is generally allowed between 6:00 a.m. and 10:00 p.m. unless otherwise posted.

Nantucket’s beaches are an important part of the island’s natural environment and are a treasure for residents and visitors alike. Drivers are expected to follow all beach access regulations and help protect sensitive coastal habitats. Access may be restricted or closed in certain areas due to erosion, nesting shorebirds, protected species, or changing beach conditions.

Before You Go

Obtain a valid Town of Nantucket beach vehicle permit
Review the official Beach Driving Map before heading out
Check for beach closures and access restrictions
Follow all posted regulations and seasonal restrictions
Stay within designated driving areas only