--- title: "NPT vs BSP Thread for Faucets: What Importers Must Specify When Sourcing from China" date: 2026-08-06T08:46:01Z modified: 2026-08-26T06:24:14Z permalink: "https://www.aimfaucet.com/blog/tech/npt-vs-bsp-thread/" type: post status: publish excerpt: "" wpid: 4251 categories: - Tech featured_image: "https://www.aimfaucet.com/wp-content/uploads/2026/08/image-67.webp" featured_image_alt: Stainless Steel Kitchen Faucet timestamp: 2026-08-26T06:24:14Z tags: - Tech --- ## **Quick Answer:** NPT and BSP are different pipe-thread systems and are not interchangeable. NPT is common in North America, while BSP is common in many European, Australian, Middle Eastern, and Asian markets. AIM can match faucet connection threads to the buyer’s target market before production. ## **Why Do Faucet Thread Standards Matter When Buying From China?** Thread choice can decide whether a faucet installs at all. Many importers focus on material, finish, [cartridge](https://www.aimfaucet.com/wp-content/uploads/wp-mfa-exports/post/high-quality-ceramic-cartridge-importance.md), and [price](https://www.aimfaucet.com/wp-content/uploads/wp-mfa-exports/post/what-affects-faucet-wholesale-price.md), then leave the connection thread unclear. That can cause problems after delivery. A faucet may look correct but fail to connect to the local [supply line](https://www.aimfaucet.com/wp-content/uploads/wp-mfa-exports/page/faucet-supply-line-size-guide.md). The buyer may face rework, adapters, returns, or project delays. Never order a faucet by size alone. Write the thread system, size, and connection type in the purchase order. ![Standards for aim kitchen stainless steel faucets](https://www.aimfaucet.com/wp-content/uploads/2026/08/image-52-1200x900.webp) ## **What Are NPT, BSP, and Metric Faucet Threads?** ### **What Is an NPT Thread?** NPT means National Pipe Thread. It is widely used in the United States and Canada. Standard NPT pipe threads are tapered and use a 60-degree thread form. The taper makes the male and female threads tighten as they turn together. Thread tape or another approved sealant is normally used where the thread makes the pressure seal. ASME B1.20.1 covers NPT dimensions and gaging. Buyers should write the exact NPT callout instead of only “1/2 inch.” ### **What Is a BSP Thread?** BSP means British Standard Pipe. BSP thread forms use a 55-degree angle. Buyers often see BSPP and BSPT. BSPP is parallel. It normally seals with a washer, O-ring, gasket, or sealing face. ISO 228-1 covers parallel pipe threads where the thread itself does not make the pressure-tight joint. BSPT is tapered. ISO 7-1 covers pipe threads where pressure-tight joints are made on the threads. ### **What Does Metric Mean for Faucet Buying?** Metric threads use metric size and pitch callouts. They may appear on parts, mounting hardware, or some domestic products made in China. Do not assume a China-made faucet uses metric [water connections](https://www.aimfaucet.com/wp-content/uploads/wp-mfa-exports/post/how-to-connect-water-hose-to-kitchen-faucet.md). Export products may use BSP or NPT based on destination. The drawing and PO should state the thread. ## **Why Are NPT and BSP Threads Not Interchangeable?** NPT and BSP can look similar, especially on small faucet connections. Buyers may find the error only during installation. | **Point** | **NPT** | **BSP** | | --- | --- | --- | | Thread angle | 60 degrees | 55 degrees | | Form | Tapered | BSPP parallel or BSPT tapered | | Common market | U.S. and Canada | Europe and other markets | | Seal | Thread sealant | Depends on BSPP or BSPT | | Standard | ASME B1.20.1 | ISO 228-1 or ISO 7-1 | A 60-degree NPT profile does not correctly match a 55-degree BSP profile. The first turns may seem to fit, but the joint can bind, leak, or damage threads. Do not force the connection. An adapter can solve an urgent problem, but it should not replace the correct production specification. ## **Which Faucet Thread Standard Is Common in Each Market?** Use the target country as a starting point, then confirm the project drawing and local requirement. - United States and Canada: NPT is common. - United Kingdom, Germany, France, and much of Europe: BSP is common. - Australia and New Zealand: BSP is common. - Saudi Arabia, UAE, Qatar, and many Middle Eastern markets: BSP is common. - Many Southeast Asian markets: BSP is common. - China: metric callouts may appear on domestic parts, while export faucets often follow destination standards. - Japan: JIS pipe-thread specifications are common and can resemble BSP, but confirm the exact JIS callout. - Brazil: NPT is common in many applications, but confirm the project specification. This is a buying guide, not a substitute for local codes or project requirements. ## **Why Do G1/2, 1/2 NPT, and DN15 Cause Ordering Mistakes?** These labels can all appear around “half-inch” plumbing, but they do not mean the same thread. G1/2 normally refers to a parallel BSP thread under ISO 228. 1/2 NPT is a tapered NPT connection under ASME B1.20.1. DN15 is a nominal pipe-size designation. It does not tell the supplier whether the connection is NPT, BSPP, BSPT, or another thread. This is why “1/2 inch faucet connection” is too vague for an export order. ## **How Can Importers Prevent Faucet Thread Mistakes?** A few checks before mass production can prevent a shipment from arriving with the wrong connection. First, write the full thread callout in the PO. Use G1/2 BSPP or 1/2 NPT, not only “1/2 inch.” Second, ask for a thread drawing. It should show the standard, male or female connection, size, and sealing method. Third, check the sample with the thread gauge. Also check hoses, angle valves, wall inlets, and adapters. The faucet may use the right thread while one accessory uses the wrong one. ## **How Does AIM Confirm Faucet Threads for Export Orders?** [ ![Pull Out Kitchen Tap With 3 Spray Modes DG21057-1](https://www-aimfaucet-com.b-cdn.net/wp-content/uploads/2026/02/Pull-Out-Kitchen-Tap-With-3-Spray-Modes-DG21057-1-1.webp) ](https://www.aimfaucet.com/product/pull-out-kitchen-tap-with-3-spray-modes-dg21057-1/) Pull Out Kitchen Tap With 3 Spray Modes DG21057-1 GET AIM’s DG21057-1 chrome pull-out kitchen tap from Coral Collection. High-arc design with 3 spray modes, 600mm reach, zinc alloy body. [View New Product](https://www.aimfaucet.com/product/pull-out-kitchen-tap-with-3-spray-modes-dg21057-1/) AIM can match connection details to the target market during order review. Buyers should give the country, project standard, thread callout, and matching plumbing parts before production. AIM’s [pull-out kitchen tap](https://www.aimfaucet.com/product/pull-out-kitchen-tap-with-3-spray-modes-dg21057-1/) lists 600 mm supply lines with G1/2 water connections. Its [kitchen sink faucet](https://www.aimfaucet.com/product/chrome-kitchen-sink-faucet-with-level-handle-dg16750/) also lists standard G1/2 supply-line connections. These examples show why the connection must be checked before export. A G1/2 version may suit a BSP market, while a North American project may need another specified connection. Send the required thread standard with the inquiry so AIM can confirm hoses, fittings, drawings, and labels before production. ## **What Should Buyers Write Before Placing the Order?** The best way to avoid an NPT vs BSP thread mistake is to make the connection part of the product specification. Never rely on appearance or the words “half inch.” State the standard, size, male or female thread, sealing method, and target market. Then verify the sample with a gauge before production. Clear PO details can prevent leaks, adapters, returns, and delays. ## FAQs ### Is BSP and NPT thread compatible? No. BSP and NPT are not compatible. They have different thread angles (BSP 55°, NPT 60°), different thread profiles (BSP has rounded peaks and valleys; NPT has flat peaks and valleys), and different pitches at most sizes. Attempting to join an NPT male to a BSP female will cause the joint to bind within a few turns and result in a spiral leak. An adapter is required to connect the two systems. ### Which is better, BSP or NPT? Neither is universally better — the right choice depends on the target market. NPT is the standard in the United States and Canada. BSP is used across Europe, the UK, Australia, the Middle East, and most other markets. For faucet export orders, the correct thread system is whichever matches the destination country’s plumbing infrastructure. Specifying the wrong system means the faucet cannot be installed without an adapter. ### Can you fit NPT to BSP? Not directly. NPT and BSP threads will partially engage — the first few turns may seem to catch — but the different thread angles (60° vs 55°) and profiles prevent a proper seal. The connection will leak under pressure. If an NPT-to-BSP connection is required in the field, use a thread adapter rated for the application. Do not force the threads or rely on sealant alone to compensate for the profile mismatch. ### Are 1/4 NPT and BSP the same? No. 1/4 NPT has 18 threads per inch. 1/4 BSP has 19 threads per inch. The thread angle also differs: NPT is 60° with flat peaks and valleys; BSP is 55° with rounded peaks and valleys. They are close in size but not interchangeable. A 1/4 NPT fitting will not make a leak-free seal in a 1/4 BSP port. ### Can you convert BSP to NPT? Yes, using a BSP-to-NPT adapter fitting. Adapters are available in standard sizes and allow connection between the two thread systems. The adapter must be rated for the application pressure and fluid type. For faucet supply lines, use an adapter with appropriate sealing — NPT connections require thread sealant tape (PTFE); BSPP connections require a washer or O-ring at the seating face. ### How to tell if a thread is BSP or NPT? Use a thread gauge or count threads per inch across a 1-inch span, then compare against a reference table. For 1/4″ size: 18 TPI = NPT, 19 TPI = BSP. Also check the thread angle: NPT has flat peaks and valleys; BSP has rounded peaks and valleys. A second check is taper: NPT is always tapered; BSP comes in both tapered (BSPT) and parallel (BSPP) forms. Measure the first and last full thread on a male fitting — if the diameter changes, it is tapered. [Get a Free Quote](https://www.aimfaucet.com/wp-content/uploads/wp-mfa-exports/page/contact-us.md)