No, three-hole faucet sizes vary by spread, hole diameter, and deck thickness.
Shopping for a replacement can feel simple until you discover the holes in your sink don’t match the new trim you love. Three mounting holes are common on bathroom sinks and kitchen decks, but the spacing between them, the hole diameters, and the deck thickness each faucet can clamp to all differ by model. This guide spells out the spreads that exist, the measurements that matter, and a quick way to confirm what will fit before you buy.
Quick Reference: Common Three-Hole Layouts
Most three-hole sinks fall into one of three patterns. Use the table below to match what you have on the counter.
| Faucet Type | Typical Center-To-Center Spread | Typical Hole Diameter |
|---|---|---|
| 4-Inch Centerset (one body or small base) | 4 in. between outer holes | About 1"–1-3/8" per hole; center often 1-3/8" |
| 4-Inch Mini-Widespread (three separate pieces) | 4 in. between handle centers | About 1-1/8"–1-3/8" per hole |
| Adjustable Widespread | Usually 8–16 in. adjustable | About 1-1/8"–1-1/2" per hole |
Are Three-Hole Sink Faucets One Size? Fit Guide
They aren’t interchangeable across the board. A three-piece widespread designed for an 8-inch or larger spread won’t land on a sink drilled for 4 inches. A compact one-piece centerset will cover a 4-inch pattern, but it can’t stretch to an 8-inch layout. Mini-widespread bridges the style gap by keeping the look of three separate pieces while still using a 4-inch layout.
What “Spread” Really Means
Spread is the center-to-center distance between the hot and cold handles (or the two outer holes). On a 4-inch layout, those centers are four inches apart. On a widespread, the manufacturer specifies a range—often any spacing from eight inches up to sixteen. That range is made possible by flexible connectors below the deck.
Why Hole Diameter Matters
Even when the spread lines up, the hole size must allow the spout shank and valve bodies to pass through and seal. Many bathroom faucets are happy with holes around 1-3/8 inches, while some centerset bodies slide through openings as tight as 1 inch. Manufacturers publish the minimum hole diameter in their install sheets; if your sink holes are larger, many kits include bushings or gaskets to center the parts. Many brand guides list 1-3/8" as a common opening for bathroom faucets, such as Kohler hole size guidance.
Deck Thickness Limits
Every model lists the maximum deck thickness it can clamp. Light porcelain tops are rarely an issue, but thick stone or integrated solid-surface tops can exceed the clamp reach. If you’re mounting on a chunky deck, check the spec sheet for a max thickness number and look for any available extension kits.
How To Measure Your Sink Quickly
Grab a tape measure and a flashlight. You’ll confirm three things in minutes.
Step 1: Check The Spread
Measure from the center of the left hole to the center of the right hole. If it reads 4 inches, your sink takes centerset or mini-widespread. If it reads around 8 inches or more, you’re in widespread territory. Many stone tops land at 8 inches exactly; some furniture vanities are drilled at 10, 12, or even wider.
Step 2: Measure Hole Diameters
Use a simple ruler or a caliper. Most bathroom holes fall between 1-1/8 inches and 1-1/2 inches. If yours are oversized, you may need trim rings or the manufacturer’s bushing to center the spout.
Step 3: Measure Deck Thickness
From the underside, measure the full deck depth at a hole. Many widespread kits clamp to about 1-1/4 inches; some go thicker, and some need an extension when the deck is heavy.
What Fits Where
Here’s the basic compatibility map so you can pick the right route on the first try.
4-Inch Sink Layouts
Two choices fit: a one-piece centerset (spout and handles integrated) or a three-piece mini-widespread. You can also run a single-hole faucet with a deck plate if the plate covers the side holes. A true 8-inch widespread won’t fit because the handle stems land too far apart for the holes you have.
8-Inch To 16-Inch Layouts
This zone is for widespread sets. The handles and spout install through separate holes and connect under the deck using flexible hoses or rigid tubes, depending on the brand. Many sets are adjustable anywhere in the range; some are fixed at eight inches. Read the spec sheet so you don’t assume adjustability where none exists.
Real-World Specs From Brands
Brands publish the exact numbers you need. A few common patterns:
- Many centerset bodies fit through a 1" minimum center hole.
- Lots of widespread sets call for 1-1/8" minimum valve holes and accept spreads from 8" to 16".
- Delta and other makers often mention that holes larger than 1-3/8" need a bushing to center the spout.
Measure First: A Printable-Style Checklist
Log the three numbers below and you’ll order with confidence.
| Measurement | What To Record | Why It Matters |
|---|---|---|
| Hole Spread | 4" or 8–16" (exact number helps) | Determines centerset/mini-widespread vs widespread |
| Hole Diameter | Each hole in inches | Confirms shanks will pass and seal |
| Deck Thickness | Depth at a hole | Confirms the clamp can reach |
Installation Notes That Avoid Hassles
Use The Right Seal
Some kits include gaskets; others expect plumber’s putty or silicone under escutcheons. Follow the brand’s sheet to avoid leaks or finish damage.
Mind The Supply Connections
Most modern bathroom faucets use 3/8" compression connections. If your shutoffs use a different size, add the proper adapter or replace the stops while the space is open.
Check Water Rules For The Fixture
Faucets sold in the U.S. must conform to performance and safety standards. When you scan a spec sheet, look for the compliance line so you know the product meets the plumbing code used in your area. In the U.S., faucets and fittings are referenced in plumbing codes to the ASME A112.18.1 standard so you can verify compliance on the spec sheet.
Common Questions Shoppers Ask
Can I Put A Three-Piece Widespread On A 4-Inch Sink?
No. The handle posts won’t land in the existing holes. Use a mini-widespread or a centerset instead. If you want the three-piece look on a 4-inch pattern, mini-widespread is designed for that exact case.
My Sink Holes Are A Little Larger Than 1-3/8". Is That A Problem?
Usually not. Many brands include a bushing or a larger base to center and seal the spout when the hole runs wide. If your holes are oversized by a lot, look for trim rings in the same finish to keep things tidy.
What About Kitchen Sinks With Three Holes?
Kitchen decks often use three holes to mount a pull-out faucet with a side sprayer or to add accessories like soap dispensers. The same measuring rules apply: check spread, hole size, and deck thickness, then match the faucet family accordingly.
Picking Between Centerset, Mini-Widespread, And Widespread
Style
Centerset reads compact and tidy, good for tight tops. Mini-widespread gives you the separate-handle look without changing the 4-inch pattern. Full widespread fills more counter space and pairs well with larger bowls or double vanities.
Ease Of Installation
Centerset slips in as one piece and usually takes the least time. Mini-widespread and widespread take a bit more patience because you align three parts and connect them under the deck. Clear a spot below the sink to make the job smoother.
Buying Checklist Before You Click “Add To Cart”
- Match the spread to your sink drilling.
- Confirm hole diameters against the spec sheet.
- Check max deck thickness and order an extension kit if needed.
- Verify connection type at the shutoffs.
- Scan the compliance line for the applicable standard.
Why You Can Trust The Measurements In This Guide
The measurements come from brand install sheets and product pages plus the plumbing code reference that cites the governing standard.
- A brand help page notes 1-3/8" sink holes are common on bathroom faucets.
The Bottom-Line Fit Advice
Three holes alone don’t define size. Match spread first, confirm hole diameters, then check deck thickness. With those three numbers in hand, you’ll pick a faucet that lands cleanly, seals tight, and meets the standard your local code expects.