What Thread Is Garden Hose: Sizes, Adapters, Guide 2026

In the U.S., garden hoses use 3/4-11.5 GHT (straight) with a washer seal.

If you have ever searched what thread is garden hose, you are not alone. I work with fittings and water systems every week. I know the pain of mismatched parts, leaks, and returns. In this guide, I break down what thread is garden hose, how it differs from pipe threads, how to measure it, and how to pick the right adapter in minutes. Expect clear steps, real examples, and expert tips you can use today.

What Garden Hose Thread Really Means

Garden hoses in the United States use a standard called GHT, short for Garden Hose Thread. The size is 3/4-11.5 GHT. It is a straight thread, not tapered. The seal happens at the flat face with a rubber washer, not on the threads.

This standard is defined in industry specs (such as ASME B1.20.7). Most outdoor spigots have a male 3/4-11.5 GHT thread. Most hose ends have a female swivel 3/4-11.5 GHT with a washer inside. If you are asking what thread is garden hose, this is the core fact you need.

Key details to remember:

• Thread type: GHT (straight/parallel)
• Nominal size: 3/4 inch
• Threads per inch: 11.5 TPI
• Seal type: flat face with a rubber washer (no tape needed)

When people ask what thread is garden hose, they also wonder about fit with pipe threads. We will cover that next.

GHT vs NPT vs BSP: Compatibility and Adapters

Not all threads are the same. Many leaks happen because of this.

• GHT (Garden Hose Thread): 3/4-11.5, straight thread, seals with a washer.
• NPT (National Pipe Taper): tapered thread, common on plumbing pipes, seals on the thread flanks with sealant or tape.
• BSP (British Standard Pipe): used in the UK, EU, AU, and more. Comes in BSPP (parallel) and BSPT (tapered). Many garden taps use G 3/4 (BSPP) with a washer seal.

Straight vs tapered matters. GHT is straight. NPT is tapered. They do not seal well together. Do not force a GHT hose onto an NPT pipe. It may seem to start, but it will leak or strip.

If you need to join systems, get the right adapter. For example:

• 3/4 NPT male to 3/4 GHT female adapter for U.S. pipe to hose.
• G 3/4 BSPP to 3/4 GHT adapter for global taps to U.S. hose.

I often carry a small kit of brass adapters. It saves jobs and avoids returns. If your search is what thread is garden hose, remember this too: knowing the difference from NPT and BSP is half the battle.

How to Identify Your Hose Thread

You can confirm what thread is garden hose at home with simple checks. I use a caliper and a small pitch gauge, but you can eyeball it too.

Steps to identify:

1. Check the sealing surface. If the female side has a flat washer, you likely have GHT or BSPP. If it needs tape to seal, you may have NPT.
2. Measure the outside diameter of a male spigot. GHT male OD is about 1.0625 inches (around 1-1/16 inches).
3. Count threads per inch. GHT uses 11.5 TPI. NPT 3/4 uses 14 TPI. BSPP 3/4 also uses 14 TPI, but has a 55-degree thread form and often needs a washer or O-ring.
4. Look for markings. Some fittings are stamped GHT, NH, NPT, or BSP.

Common signs you actually have GHT:

• Female swivel with a captive washer.
• Connects by hand, then seals drip-free without tape.
• Marked GHT or NH (sometimes listed as “3/4 NH”).

Asking what thread is garden hose is smart. A two-minute check here can prevent a weekend of leaks.

Hose Sizes, Fittings, and Flow

Thread size is not the same as hose inside diameter. This trips up many buyers.

Common hose IDs:

• 1/2 inch: light duty, lower flow, good for small yards.
• 5/8 inch: most common for home use. Good balance of pressure and flow.
• 3/4 inch: high flow for long runs, washers, and pressure loss control.

Ends and accessories:

• Female hose end: 3/4-11.5 GHT with washer.
• Male hose end: 3/4-11.5 GHT.
• Nozzles, sprinklers, filters, and timers: usually 3/4 GHT. Always check product specs.

Typical materials:

• Brass: strong, long life, threads hold up well.
• Aluminum: light, can gall if forced.
• Plastic: light and cheap, but watch for cross-threading.

If your question is what thread is garden hose, remember that most consumer hose hardware in the U.S. is 3/4-11.5 GHT, regardless of hose ID.

Installation Tips, Sealing, and Leak Prevention

I have seen most leaks come from two things: no washer or the wrong thread.

Do this every time:

• Use a fresh rubber washer in the female hose end.
• Hand-tighten first. Stop when the washer seats. No tools needed in most cases.
• Do not use PTFE tape on GHT joints. The seal is at the washer, not the threads.
• If a joint leaks, replace the washer. If it still leaks, check that you did not mix GHT with NPT or BSP.

Mistakes to avoid from my field notes:

• Cross-threading plastic parts by starting crooked.
• Forcing a tapered NPT piece into a GHT fitting.
• Using old, flattened washers and expecting a seal.

If you ever type what thread is garden hose because of a leak, check the washer first. It solves most issues in seconds.

International Variations and Travel Adapters

Outside North America, faucets often use BSP threads, not GHT. In the UK and EU, garden taps are often G 3/4 (BSPP). Many quick connectors snap onto a G 3/4 male adapter at the tap.

Traveling with gear?

• U.S. hose to EU/UK tap: use a G 3/4 BSPP female to 3/4 GHT male adapter.
• EU/UK hose to U.S. spigot: use a 3/4 GHT female to G 3/4 BSPP male adapter.

If your search intent is what thread is garden hose, note that the phrase points to the U.S. GHT standard. For global use, confirm local BSP specs, or buy a mixed adapter kit. It will save you a second trip to the store.

Measurement Reference and Standards

If you want to go deeper and verify, use these checks.

Simple checks:

• Measure male OD near 1.0625 inches for 3/4 GHT.
• Count 11.5 threads per inch.
• Confirm a flat-face seal with a rubber washer.

Standards and naming:

• GHT is often listed as NH (National Hose) in catalogs.
• The geometry is defined by industry standards used by major manufacturers.
• Adapters often list “3/4 GHT x 3/4 NPT.” Read both sides before you buy.

I keep a small thread pitch gauge, a caliper, and spare washers in my truck. This kit has answered many “what thread is garden hose” site calls without delay.

Real-World Examples: What Works and What Fails

From my jobs and yard work, a few clear lessons stand out.

What works:

• Brass GHT fittings with fresh EPDM washers. They seal fast and last long.
• Short leader hoses with GHT ends for tight spaces at the spigot.
• Proper GHT backflow preventers and vacuum breakers rated for outdoor use.

What fails:

• Mixing 3/4 NPT and 3/4 GHT. The sizes look “close,” but the seal fails.
• Over-tightening metal-to-plastic joints. Threads deform and leak later.
• Ignoring a crushed washer. It drips today and floods tomorrow.

If you still wonder what thread is garden hose after this, try one test: swap in a new washer on a clean GHT joint. If it still leaks, you likely have the wrong thread system.

Frequently Asked Questions of what thread is garden hose

What thread is garden hose in the U.S.?

Garden hoses use 3/4-11.5 GHT, which is a straight thread. The seal is made with a flat washer in the female hose end.

Is garden hose thread the same as NPT?

No. GHT is straight and seals with a washer, while NPT is tapered and seals on the threads. They are not compatible without an adapter.

Can I use Teflon tape on garden hose threads?

You do not need it. GHT seals at the washer, so tape does not help and can even hinder sealing.

How do I adapt a garden hose to a pipe fitting?

Use a GHT-to-NPT adapter of the right size, such as 3/4 GHT female to 3/4 NPT male. Brass adapters are durable and seal well with a proper washer.

What is the outside diameter of a 3/4 GHT male thread?

It is about 1.0625 inches, or roughly 1-1/16 inches. This helps you confirm you have GHT.

Do European garden taps use the same thread as U.S. hoses?

Usually not. Many EU and UK taps use G 3/4 BSPP, so you need a BSP-to-GHT adapter to use a U.S. hose.

Why does my garden hose connection leak even when tight?

The washer may be missing, old, or damaged. Replace the washer first; if it still leaks, check for a thread mismatch.

Conclusion

Most U.S. garden hoses use a simple, reliable standard: 3/4-11.5 GHT with a washer seal. When you know what thread is garden hose, you can buy the right parts, avoid leaks, and skip the returns. Measure once, use a fresh washer, and match GHT to GHT or use the correct adapter.

Put these steps to work today. Check your spigot, confirm your fittings, and keep a few washers and adapters on hand. If this helped answer what thread is garden hose, share it with a neighbor, subscribe for more practical guides, or leave a question and I will help you solve it.