Red, right, returning gets you most of the way, but Florida adds two twists: the Intracoastal Waterway has its own yellow symbols, and on the Gulf coast "returning" doesn't always mean what it sounds like. This guide covers what each marker means, how the ICW changes it, and the white-and-orange signs that tell you to slow down or stay out.
Red, right, returning
Channel markers come in pairs of meaning, not pairs of posts. When you're heading in from the sea (the Coast Guard calls this the conventional direction), red markers mark the right side of the channel and green markers mark the left. Keep red on your right and green on your left and you're in the channel. Heading back out, flip it: red on your left.
You can tell the two apart by shape as well as color, which helps in glare or at dusk. Red markers are even-numbered and are either triangle signs on a post (daybeacons) or cone-topped floating buoys called nuns. Green markers are odd-numbered and are either square signs on a post or flat-topped buoys called cans. The numbers get bigger as you head in, so 1 and 2 are nearest the sea and higher numbers are farther up the channel. If a marker is lit, red markers show red lights and green markers show green lights.
- Red, even number, triangle or nun: keep it on your right heading in.
- Green, odd number, square or can: keep it on your left heading in.
- Numbers climb as you head in, so falling numbers mean you're heading out.
Where two channels split
A marker with red and green horizontal bands is a junction marker (officially a preferred channel mark). It means the channel splits there, and the top band tells you which branch is the preferred channel. If the top band is green, treat it as a green marker to follow the preferred channel. If the top band is red, treat it as a red marker. You can pass on either side, but check the chart first, because these also sit on wrecks and obstructions.
The ICW's yellow symbols
The Intracoastal Waterway (ICW) is the protected inside route along both of Florida's coasts. Its markers look like normal red and green markers but carry a small yellow symbol, and that symbol is what you follow when you're running the ICW. These meanings apply when you're heading the ICW's own direction: south along the Atlantic coast, west across the Okeechobee Waterway, and west along the Gulf coast toward Texas. Heading the other way, they flip.
This matters most where the ICW crosses an inlet or a channel that runs out to sea. There, the red and green colors and the numbers belong to the crossing channel, and the yellow symbol tells ICW traffic which side to pass on. A red marker can carry a yellow square, and when it does, ICW traffic heading the ICW's direction keeps it on the left. Trust the yellow symbol when you're on the ICW, and trust the color when you're on the crossing channel.
- Yellow triangle: heading the ICW's direction, keep it on your right, whatever the marker's color or number.
- Yellow square: heading the ICW's direction, keep it on your left, whatever the marker's color or number.
- Yellow horizontal band: tells you the marker is part of the ICW, but not which side to pass on.
Which way is "returning" on the ICW?
On the ICW there's no sea to return from, so the Coast Guard assigns a direction. It runs clockwise around the country: south down the Atlantic coast, west across the Okeechobee Waterway, and from Florida toward Texas along the Gulf. On Florida's east coast, red is on your right as you head south. Along the Gulf coast, red is on your right as you head toward Texas, which along Florida's west coast generally means north and then west into the Panhandle.
That's the opposite of what many boaters expect on the Gulf side, and it's why the yellow symbols and the chart matter more than the slogan. Where the direction isn't obvious, the federal rule tells boaters to check the chart, and that's the right habit. Use a current NOAA chart or a chart-plotter app for the water you're running.
Other markers you'll see
A few markers have nothing to do with which side of the channel you're on:
- Red and white vertical stripes: safe water. There's open water all around it, and it often marks the seaward end of a channel or the middle of a fairway.
- Black with red bands and two black balls on top: an isolated danger, such as a rock or wreck, with water all around it. Don't pass close.
- Solid yellow: a special mark for an anchorage, a cable area or a similar feature. It has no lateral meaning.
- White with a blue band: a mooring buoy. It isn't a channel marker.
White-and-orange signs: slow down or stay out
White signs and buoys with orange shapes are information and regulatory markers. In Florida these are how speed and manatee zones, no-wake areas and closed areas are posted, so they're the ones most likely to get you a ticket:
- Orange circle: a restriction applies in this area. The words inside tell you which one, for example Slow Speed, Idle Speed or a manatee zone.
- Orange diamond: danger, such as rocks, shoals or a submerged hazard.
- Orange diamond with a cross inside: boats keep out, for example a swim area or a dam.
- Orange square or rectangle: information, such as directions or the name of a place.
Before you go
Markers get knocked off station by storms and boat strikes, and channels shift, so treat any single marker as a hint and the chart as the plan. If you see a damaged or missing marker, report it to the Coast Guard or to FWC. Our radar page shows FWC manatee protection zones, and New to Boating in Florida covers the rest of the basics.