What is a basin wrench, and how do you use one?
In this guide
A basin wrench is a plumbing wrench with a long shaft and a self-gripping jaw that pivots at the top. It reaches up into the cramped space behind a sink to turn faucet nuts. Plumbers also call it a sink wrench or a faucet wrench.
This guide is part of our hand tools hub. For the rest of the wrench family, see types of wrenches.
Parts of a basin wrench
| Part | What it does |
|---|---|
| T-handle | Slides through the bottom of the shaft so you can turn it with both hands |
| Shaft | Fixed or telescoping; reaches up behind the bowl |
| Head and pivot | The jaw assembly swings on a pin, so it can sit flat on the nut at an angle |
| Curved jaw | Toothed and often spring-loaded; wraps around the nut |
| Flip feature | Turn the jaw over to the other side to change direction |
RIDGID's telescoping model extends from 10 to 17 inches. Its jaw grips nuts from 3/8 to 1-1/4 inch.
How the jaw grips
The curved jaw is pinned so it pulls tighter as you turn. The harder you twist, the harder it bites. That's how one jaw grips many nut sizes with no adjusting screw. US patent 4,485,702, for a basin wrench, describes the movable jaw pinned to a yoke so it can flip to the other side of the fixed jaw.
The catch: it only grips one way. To turn the other way, you flip the jaw over.
What a basin wrench is used for
- Faucet mounting nuts. These clamp the faucet to the sink or counter. Moen's faucet guide names a basin wrench for removing old mounting nuts.
- Supply-line nuts. The nuts that join the supply hoses to the faucet shanks.
- Tightening during install. Moen's lavatory sheet uses a basin wrench on the bottom nuts, while a second wrench holds the valve body still.
- Other tight spots. Any nut you can reach straight up to but can't swing a wrench around.
Putting a new sink into a laminate counter? You cut the opening first, often with a jigsaw. Our jigsaw circle guide covers the round cuts for a bar sink.
How to use a basin wrench
- Shut off the water at the stop valves and open the faucet to drain it.
- Set the direction. Flip the jaw so the open side faces the way you want to turn. To loosen, you turn counterclockwise as seen from below.
- Extend the shaft if it telescopes, so the handle hangs below the sink edge.
- Hook the jaw around the nut. Push up so the jaw sits flat on the nut, not tilted.
- Turn the T-handle. The jaw bites as you turn. If it slips, stop and reseat it.
- Ratchet back. At the end of a swing, loosen your grip, rotate back, and take another bite.
- Hold the faucet still from above, or have a helper hold it, so the whole faucet doesn't spin.
Basin wrench won't grip or won't fit?
| Problem | Likely cause | Fix |
|---|---|---|
| Jaw slips around the nut | Jaw flipped the wrong way | Flip it and try again |
| Jaw slips after a bite | Jaw not flat on the nut | Push up harder; angle the shaft straight |
| Won't bite at all | Plastic nut with wings or slots | Turn it by hand, or use the faucet's own tool |
| Won't open wide enough | Nut is over 1-1/4 inch | Use the faucet maker's tool or large pliers |
| Can't reach | Shaft too short | Use a telescoping wrench |
| Nut won't move | Corrosion | Penetrating oil on metal nuts; for plastic, Moen suggests a hair dryer |
Some faucets use big plastic nuts with wings, made to turn by hand. Some Moen faucets come with a plastic tool that slides over the nut and turns with a screwdriver (see types of screwdrivers). If you have that tool, use it. More ways around a stuck faucet nut are in our spanner nut guide.
Types of basin wrenches
| Type | Good for | Notes |
|---|---|---|
| Fixed shaft | Most bathroom sinks | Simple and cheap |
| Telescoping | Deep kitchen sinks, vanities with a back panel | Extends to reach; RIDGID's is 10 to 17 inches |
| With a built-in light | Dark cabinets | RIDGID's 2017 adds an LED |
| Faucet installer tool | Plastic nuts and supply nuts | A tube with sockets at each end; not a true basin wrench |
Basin wrench vs similar tools
| Tool | Reaches behind a sink? | Self-gripping? | Best use |
|---|---|---|---|
| Basin wrench | Yes | Yes | Faucet and supply nuts behind the bowl |
| Adjustable wrench | Rarely | No | Nuts you can reach from the side |
| Tongue-and-groove pliers | Sometimes | No | Slip nuts on drain traps |
| Pipe wrench | No | Yes | Threaded pipe, out in the open |
| Strap wrench | Sometimes | Yes | Round, soft or shiny parts |
Pliers are covered in our types of pliers guide. When a part needs an exact tightness, as on cars and machines, use a torque wrench instead.
How to choose one
- For one bathroom faucet, a basic fixed-shaft basin wrench is enough.
- For kitchen sinks and deep vanities, get a telescoping model.
- For plastic-nut faucets, check what came in the box first. You may not need a basin wrench at all.
- Check the capacity. RIDGID lists 3/8 to 1-1/4 inch. Make sure your nut is in range.
Keep it with your plumbing kit. Our toolbox guide shows how to set up job kits so the right tool is there when the faucet drips.
Key takeaways
- A basin wrench turns faucet mounting nuts and supply-line nuts in the tight space behind a sink bowl.
- Its curved jaw pivots, so it bites harder the more you turn. Flip the jaw over to switch between loosening and tightening.
- RIDGID's telescoping basin wrench grips 3/8 to 1-1/4 inch nuts and extends from 10 to 17 inches.
- If it won't grip, the jaw is flipped the wrong way or the nut is plastic with wings. Flip it, or turn the plastic nut by hand.
- For new faucets, read the sheet first. Some Moen faucets ship with their own plastic nut tool.
Questions people ask
What is a basin wrench used for?
Turning the nuts that hold a faucet to a sink, and the nuts on faucet supply lines. They sit up behind the bowl, where a normal wrench has no room to swing.
How do you use a basin wrench?
Flip the jaw so its open side faces the way you want to turn. Hook it around the nut, push the shaft up so the jaw sits flat, and turn the T-handle. Counterclockwise loosens, as seen from below.
Why won't my basin wrench grip?
The jaw is facing the wrong way, it isn't sitting flat on the nut, or the nut is plastic with wings that the jaw can't bite. Flip the jaw, reseat it, or turn a plastic nut by hand.
Why won't my basin wrench fit the nut?
The nut may be bigger than the jaw opens. RIDGID's basin wrench tops out at 1-1/4 inch. Some faucets use large plastic nuts made for a special tool or for your hand.
Can I use pliers instead of a basin wrench?
Sometimes, if you can reach the nut and swing the handles. Behind most sinks you can't. Our guide to removing a spanner nut without a wrench lists other options.
Is a basin wrench the same as a sink wrench?
Yes. Basin wrench, sink wrench and faucet wrench usually mean the same tool.
Sources
- RIDGID telescoping basin wrench: capacity and length
- RIDGID basin wrench parts sheet (models 1017, 2017: 3/8 to 1-1/4 in capacity, 10 to 17 in long)
- Moen: DIY kitchen faucet installation guide (basin wrench for mounting nuts; hair dryer on stuck plastic nuts)
- Moen MT129B lavatory faucet installation: basin wrench on the bottom nuts, hold the valve body with a second wrench
- US Patent 4,485,702: Positive action basin wrench (jaw pinned to a yoke, flips to either side)
Change log: Nov 6, 2026: Rewritten from the 2024 archive post. Fixed the old description of an 'adjustable head'; added how the pivoting jaw works, step-by-step use, RIDGID specs, and fixes for a wrench that won't grip or fit.
