What is a pitless adapter?

A pitless adapter is a fitting that connects the drop pipe inside a well casing to the underground service line below the frost line. It allows water to flow to the home without the need for a well pit.

How do I know what size adapter to buy?

Match the adapter to your drop pipe size (commonly 1", 1¼", 1½", or 2") and your casing diameter. Use our Quick Decision Guide for a personalized recommendation.

Brass vs. no-lead bronze vs. stainless — Which do I need?

Brass is the affordable standard. No-lead bronze is built for long-term durability. Stainless steel is best for corrosive water, high pressure, or agricultural use.

Can I install a pitless adapter myself?

Many DIYers install pitless adapters themselves, but it requires drilling the casing and sealing correctly. Follow local code and, if you're unsure, hire a licensed well contractor.

How long does a pitless adapter last?

A properly installed Merrill pitless adapter can last the lifetime of the well — often 30+ years — with minimal maintenance.

Where can I buy Merrill pitless adapters?

Merrill Manufacturing products are available through well and plumbing distributors nationwide. Visit merrillmfg.com to find a distributor or shop online.

The Pitless Adapter Guide

PICK THE RIGHT PITLESS ADAPTER THE FIRST TIME.

Learn how pitless adapters work, compare your options, and choose the right one with confidence.

Find My Adapter How It Works

Trusted by well professionals since 1949

Side-by-side comparison of a Merrill no-lead brass pitless adapter and a stainless steel pitless adapter

How a Pitless Adapter Works

One fitting. Two jobs.

A pitless adapter connects the drop pipe inside the well to the underground service line below the frost line. It creates a sealed, frost-proof connection and allows the pump to be removed without digging.

Cutaway view of a pitless adapter installed in a well casing showing pull pipe, o-ring seal, sealing gaskets, drop pipe, and service line

Frost-Proof Connection

Installed below the frost line to help prevent freezing.

Watertight Seal

O-rings and sealing gaskets help create a watertight seal where the service line exits the well casing.

Easy Pump Removal

Lift the pull pipe to remove the drop pipe and pump without excavation.

Quick Decision Guide

Answer 3 questions. Get your adapter.

No guesswork. Tell us your pipe size, application, and water conditions — we'll point you to the right Merrill pitless adapter.

Step 1 of 3

What's your drop pipe size?

FAQ

Answers to the questions we hear most.

Still stuck? Merrill's technical team has been helping well pros since 1949.

Contact Merrill

Ready to install?

Get your Merrill pitless adapter.

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