Why is my outdoor faucet leaking?
Updated August 2026
An outdoor faucet drip almost always traces to worn stem packing or a hardened seat washer inside the valve, a $5 fix that lets it weep from the handle or the spout. Where it leaks tells you which: from the handle while the water is on means packing; from the spout while it is off means the washer. A freeze-split frost-free bib is the expensive exception, since it leaks inside the wall where you cannot see it. Note when and where it drips before you take anything apart.
Safety first: a frost-free bib that leaks only inside the wall while the water runs can rot framing for weeks unseen, so if the bib is dry outside but a wall or ceiling below it is damp, shut off the branch feeding it and open the wall to check before it becomes hidden water damage.
Causes, most likely first
| Cause | How likely | The fix | Typical cost |
|---|---|---|---|
| Worn stem packing (drips at the handle when open) | Most common | Tighten the packing nut a quarter turn, or replace the packing washer or O-ring behind the handle. | $5–15 |
| Worn seat washer (drips from the spout when off) | Common | Back out the stem and replace the rubber washer at the valve seat. | $5–20 |
| Failed anti-siphon vacuum breaker cap | Common | Rebuild or replace the vacuum-breaker cap on top that spits water when a hose is running. | $8–25 |
| Freeze-burst frost-free bib | Occasional | A cracked frost-free stem leaks into the wall while the water runs; replace the whole bib. | $150–350 |
| Corroded or cracked valve body | Rare | A split soldered or threaded body cannot be sealed, so the bib gets replaced. | $150–350 |
Check these first
- Note where and when it leaks: from the handle while open is packing; from the spout while off is the seat washer.
- Tighten the packing nut behind the handle a quarter turn and test it again.
- Disconnect any hose; water spitting from the top cap while running is the vacuum breaker, not the valve.
- On a frost-free bib, check inside for a wet wall or ceiling, since a cracked one leaks indoors.
- Shut off the indoor branch valve feeding the bib before any teardown.
Prevent it next time
Freeze damage is the costly failure, and it is preventable. Disconnect hoses and drain the bib every fall on the winterizing schedule, the single habit that saves a $150–350 frost-free replacement; the hose bib checklist and our guide to what a hose bib is cover the vacuum-breaker and washer checks. Leaving a hose attached over winter traps water in the bib and is the classic way it splits, as our cost of a connected hose spells out.
When to call a pro
Call a plumber when a frost-free bib has cracked and leaks inside the wall, or when the bib is soldered to copper and needs replacing, roughly $150–350 with labor. Repacking the stem or swapping a washer or a vacuum-breaker cap is a $5–25 DIY with a wrench. But a leak you see only as a damp interior wall while the water runs means the pipe has split inside, and that gets opened up and replaced properly rather than patched.
Most of the causes above are maintenance problems wearing a disguise. OnOtto keeps the boring prevention on schedule so the 2 a.m. version doesn't happen.
Stop chasing symptoms, free for 30 daysFrequently asked questions
Why does my outdoor faucet leak only when the hose is attached?
That points to the anti-siphon vacuum breaker at the top of the spigot, a code-required part that stops garden water from being drawn back into your supply. Its little valve or gasket wears out and spits water past the cap when back-pressure from a hose builds. A vacuum-breaker repair kit runs about $8–25 and swaps in minutes. If the leak is at the spout itself only with the hose on, check the hose washer and the connection first.
Can I fix a leaking hose bib myself without replacing it?
Usually, yes. A drip from the handle while the water is on is worn stem packing: tighten the packing nut a quarter turn, or replace the packing or O-ring for a few dollars. A drip from the spout when it is off is the seat washer, another cheap swap. Only a cracked body or a freeze-split frost-free bib needs full replacement. Shut off the branch feeding the bib, pull the stem, and match the parts at a hardware store.
Why is my spigot leaking from the top when I turn it on?
Water weeping from under the handle or the packing nut as you open the valve is the stem packing failing to seal around the moving shaft. Snug the packing nut a quarter turn first; if that does not stop it, back the valve out and replace the packing washer or graphite packing, a job under $10. If it sprays from the very top cap only while a hose runs, that is the vacuum breaker instead, a different but equally cheap fix.
Did leaving a hose connected over winter crack my hose bib?
Very likely. A connected hose traps water in the bib and in the frost-free stem that reaches back into the warm wall. When it freezes, the water expands and splits the pipe or the internal seat, and you often do not notice until spring, when turning it on leaks inside the wall. Disconnect and drain hoses every fall, and replace a split frost-free bib, $150–350 installed, before the hidden leak rots the framing behind it.