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Carriage Bolts
Flat Head Carriage Bolts

Best Flat Head Carriage Bolts of 2026

Name: National Hardware Carriage Bolts and Nuts 12 Pack
Brand: National Hardware

Corey Phillips

Last Updated: 5 Feb 2026

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Flat Head Carriage Bolts are a type of fastener commonly used in construction, woodworking, and automotive industries. These bolts have a flat, round head with a square neck that prevents the bolt from turning as it is tightened. They are designed to be used with a nut and washer and are commonly used to attach wood or metal components to one another. Flat Head Carriage Bolts are available in a range of sizes and materials, making them suitable for various applications. They are a reliable and sturdy option for those looking for a secure fastening solution.

At a Glance: Our Top Picks

#TOP 1

National Hardware Carriage Bolts and Nuts 12 Pack

9.9

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#TOP 2

30pcs Carriage Bolts and Nuts Flat Washers Kit, M6X35 304 Stainless Steel Round Head Square Neck Carriage Bolts Screws and Hex Nuts

9.8

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#TOP 3

30pcs Stainless Steel Carriage Bolt Kit

9.6

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Top 10 Flat Head Carriage Bolts

#TOP 1

National Hardware Carriage Bolts and Nuts 12 Pack

National Hardware
N280-859
Zinc Plated
1/4" - 20 x 1-3/4"

National Hardware N280-859 V7652 Flat Head Carriage Bolts and Nuts in Zinc plated, 12 pack,1/4" - 20 x 1-3/4"

The National Hardware Carriage Bolts are designed for versatile use on wood or steel surfaces. Their unique design prevents spinning during installation and tightening, making the process much easier for you. You can tighten these bolts without needing access to both sides of the door, which adds convenience, especially in tight spaces. These bolts are specifically tailored for wood or steel garage doors, ensuring a secure fit and reliable performance for your projects.

9.9

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What We Like

Prevents spinning during installation
Tightens from one side
Suitable for garage doors
Versatile use on wood or steel

#TOP 2

30pcs Carriage Bolts and Nuts Flat Washers Kit, M6X35 304 Stainless Steel Round Head Square Neck Carriage Bolts Screws and Hex Nuts

JUTTAUTO
Jutta-G0341
Sliver

30pcs Carriage Bolts and Nuts Flat Washers Kit, M6X35 304 Stainless Steel Round Head Square Neck Carriage Bolts Screws and Hex Nuts for Home Office Industrial Electronic Hardwood Bench Slat Fixings

Features

Secure And Reliable Fastening: Round Head Design And Square Neck Of These Carriage Bolts Enable A Secure And Self Locking Fit When Appiled In Square Holes; The Combination Of The Bolts' Useful Shape And The Accompanying Hex Nuts And Flat Washers Ensures Reliable And Stable Fastening For Your Projects.Carriage Bolts Are Commonly Used In The Construction Of Furniture, Particularly Outdoor Furniture.
Optimal Dimensions: The Bolt Head Diameter Is Approximately 0.59 Inches (15 Mm), While The Round Head Height Is About 0.14 Inches (3.5 Mm); The Overall Screw Length, Including The Neck, Is Around 35 Mm; These Precise Dimensions Ensure Compatibility With A Wide Range Of Applications And Ensure Reliable Performance
Widely Application:Carriage Bolts Are Often Used In Construction Projects To Fasten Wood Or Metal Together. They Are Particularly Useful For Fastening Wood To Metal, As The Square Neck On The Bolt Prevents It From Turning When The Nut Is Tightened.Carriage Bolts Are Sometimes Used In Marine Applications, Such As The Construction Of Boats And Other Watercraft. They Are Resistant To Corrosion, Making Them Suitable For Use In Saltwater Environments;they Are Also Used In The Construction Of Industrial Equipment, Such As Conveyor Systems And Other Types Of Machinery

9.8

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#TOP 3

30pcs Stainless Steel Carriage Bolt Kit

Etomvoop
ET-MSL-GB3382
Silver

30pcs Carriage Bolts and Nuts Flat Washers Kit, M6X35 304 Stainless Steel Round Head Square Neck Carriage Bolts Screws and Hex Nuts for Home Office Industrial Electronic Hardwood Bench Slat Fixings

The Etomvoop Bolt and Nut Set offers a secure fastening solution with its round head design and square neck, ensuring a self-locking fit in square holes. You can rely on the high-quality 304 stainless steel materials for excellent corrosion resistance, making it perfect for outdoor use. This fully mounting kit includes 30 carriage bolts, nuts, and flat washers, providing ample supply for your projects. With precise dimensions, these bolts are compatible with various applications, making them ideal for wood-to-wood and wood-to-metal fastening.

9.6

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What We Like

Secure and self-locking fit
Corrosion-resistant materials
Comprehensive mounting kit
Compatible with various applications

#TOP 4 Best Merriway Carriage Bolt

Merriway Carriage Bolts with Nuts Pack

Merriway
BH04826
zinc plated
Pack of 10

Merriway BH04826 (10 Pcs) Carriage Bolts with Nuts, M6 x 100 mm (1/4 Inch x 4 Inch), Zinc Plated - Pack of 10 Pieces

The Merriway Carriage Bolts are a pack of ten M6 x 100 mm bolts featuring a round head and square neck design. These bolts are ideal for providing a secure fastening solution for various projects, ensuring stability in your assemblies. The inclusion of nuts enhances convenience, allowing for straightforward installation. Additionally, following the provided instructions ensures proper assembly and maintenance, giving you peace of mind in your DIY tasks.

9.6

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What We Like

Pack of ten bolts
Round head design
Square neck for stability
Includes nuts for convenience
Easy to follow instructions

#TOP 5

24 Set Carriage Bolts and Nuts Flat Washers Kit, M6X35 304 Stainless Steel Round Head Square Neck Carriage Bolts Screws and Hex Nuts

NEW-YIJUNSHUN
Garden Bench Slat Fixing Kit
silver

24 Set Carriage Bolts and Nuts Flat Washers Kit, M6X35 304 Stainless Steel Round Head Square Neck Carriage Bolts Screws and Hex Nuts for Home Office Industrial Electronic Hardwood Bench Slat Fixings

Features

PERFECT SIZE: Our Bolt Head Diameter Is Approximately 0.59" (15mm), Round Head Height Is Approximately 0.14" (3.5mm); Total Screw Length (including Neck) Is Approximately 35mm; These Precise Dimensions Ensure Compatibility With A Wide Range Of Applications And Ensuring Reliable Performance
HIGH MATERIAL--- The Nuts And Flat Washers Are Made Of High-Quality 304 Stainless Steel With Smooth Edges And Good Corrosion Resistance In Harsh Environments. Ideal For Securing Outdoor Chairs
Wide Range Of Applications: Carriage Bolts And Nuts Flat Washers Kit Is Particularly Suitable For Fastening Wood To Metal.

9.5

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#TOP 6

ForgeFix Carriage Bolts | M10 x 100mm

Forgefix
CB10100M
Silver
M10 x 100mm

ForgeFix Carriage Bolts | M10 x 100mm | Zinc Plated | Bag 10

Features

Ideally Suited For Timber To Timber Joining
A Round Head And A Square Neck That Prevents The Bolt From Turning While The Nut Is Tightened.
Zinc Plated To Increase Resistance To Corrosion

9.3

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#TOP 7

Luomorgo 6 Sets 3/8"-16 x 2 in. Carriage Bolts, Round Head Square Neck Fully Threaded Screws, Galvanized Steel Carriage Bolts with Hex Nuts, Flat Washers

Luomorgo
HAO0252000001
Silver
3/8"-16 x 2 in.

Luomorgo 6 Sets 3/8"-16 x 2 in. Carriage Bolts, Round Head Square Neck Fully Threaded Screws, Galvanized Steel Carriage Bolts with Hex Nuts, Flat Washers

Features

Carriage Bolt Dimension: Head Diameter: 0.78"/19.86mm Approx., Total Length: 2", Thread Size: 3/8"-16, Thread Pitch: 16 TPI, Square Neck Length: 0.17"/4.5mm.
Package Included: Set Of 6, 6 X 3/8"-16 X 2 In. Carriage Bolts With 6 X Hex Nuts, 6 X Flat Washers.
Widely Used: Carriage Bolts Are High-Strength To Use Indoor And Outdoor, Widely Used For Office Appliances, Communication Equipment, Ship Assembly, Machinery Industry And Etc.

9.2

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#TOP 8

Merriway Carriage Bolts with Nuts Pack

Merriway
BH04831
Silver
Pack of 25

Merriway BH04831 (25 Pcs) Carriage Bolts with Nuts, M8 x 75mm (5/16 inch x 3 inch) Zinc Plated - Pack of 25 Pieces

The Merriway Carriage Bolts are a pack of 25 M8 x 75mm zinc plated bolts that feature a round head and square neck. These bolts are perfect for various fixing and assembly projects, providing a secure fit for your needs. The included nuts ensure a complete solution for fastening, giving you everything you need in one pack. Following the included instructions will help you achieve the best results, making your tasks easier and more efficient.

9.1

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What We Like

Pack of 25 pieces
Round head design
Square neck for secure fitting
Zinc plated for durability
Includes nuts for convenience

#TOP 9 Best Forgefix Carriage Bolt

ForgeFix M6 Carriage Bolts 130mm Bag of 10

Forgefix
FORCB6130M
Silver
M6 x 130mm

ForgeFix Carriage Bolts | M6 x 130mm | Zinc Plated | Bag 10

The ForgeFix Carriage Bolts are designed to meet DIN603 and DIN934 standards, ensuring high quality and reliability. Their fully threaded design extends up to 100mm, making them versatile for various applications. These bolts, also known as coach bolts, feature a square section beneath the dome head that prevents rotation when tightened, providing you with a secure fastening. Primarily used for joining timber to timber, these bolts offer convenience and efficiency for your woodworking projects.

9.1

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What We Like

Meets industry standards
Fully threaded for versatility
Prevents rotation during tightening
Ideal for timber applications

#TOP 10

Merriway BH04823 Carriage Bolts with Nuts

Merriway
BH04823
Zinc Plated
Pack of 25

Merriway BH04823 (25 Pcs) Carriage Bolts with Nuts, M6 x 50mm (1/4 inch x 2 inch) Zinc Plated - Pack of 25 Pieces

Features

Round Head & Square Neck
Pack Of 25 X Carriage Bolt & Nut ZP M6 X 50mm
Nuts, Bolts & Accessories

9.1

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Editor's Notes

During our flat head carriage bolt research, we found 306 flat head carriage bolt products and shortlisted 10 quality products. We collected and analyzed 7,820 customer reviews through our big data system to write the flat head carriage bolts list. We found that most customers choose flat head carriage bolts with an average price of £5.13.

The flat head carriage bolts are available for purchase. We have researched hundreds of brands and picked the top brands of flat head carriage bolts, including National Hardware, JUTTAUTO, Etomvoop, Merriway, NEW-YIJUNSHUN.

Written by

Corey Phillips

Corey Philips is an electrician and lighting expert. He graduated from the University of Birmingham in 2012 with a Bachelor's degree in electrical and electronics engineering. Corey is a specialist contractor in lights. He sells and installs and recommends lights and lamp sheds, and other lights accessories. Aside from that, Corey is vast in installing and maintaining electrical appliances like air conditioners, water heaters, and the likes.