Best Steel Square Head Bolts in 2026
Daisy
Last Updated: Jul 17, 2026
Daisy
Last Updated: Jul 17, 2026
* PickSmartly editors independently research, review, and endorse the top products through comprehensive data analysis. We may earn a commission for qualifying purchases made through our product links.
| SELLER | SELLER SCORE | AMAZON FULFILLED | PRIME | FREE SHIPPING |
|---|---|---|---|---|
| Bolt Dropper | 9.93 | ✅ | ✅ | ✅ |
【High Quality Stainless】These Pan Head Sheet Metal Screws are 100% 410 Stainless Steel which is one of the highest forms of corrosion resistant steel, making it last longer than other hardware on the market today.
【SELF TAPPING】Our hardware is very strong and is great for both indoor and outdoor use. The stainless steel is superior to regular steel and provides excellent rust resistance in water applications. Our screws have deep cut Square Drive so stripping heads is a thing of the past!
【Dimensions】Diameter: #8 | Length: 3/4” | Thread Type: Coarse (standard) | Quantity: 100 pcs | Material: 410 Stainless Steel Commercial grade by Bolt Dropper
【Great To Keep Around】Bolt Dropper hardware is great to have around for use with sheet metal and wet environments. Bolt Dropper hardware is the highest quality available on the market and we stand by our claim 100%. They are strong, corrosion resistant and will support all of your projects.
【LIFETIME GUARANTEE】Our products are 100% stainless steel. We are so confident that our product is the best on the market that we offer a No Hassle Lifetime Guarantee.
| SELLER | SELLER SCORE | AMAZON FULFILLED | PRIME | FREE SHIPPING |
|---|---|---|---|---|
| Eastlo | 9.92 | ✅ | ✅ | ✅ |
Contents: 25 PCS 1/4-20 x 1-1/2 inch carriage bolt with round domed head and suqare neck
Screw Length: 1-1/2 inch or 38mm (measured from under the round head, including the neck height)
Big round domed head designed to eliminate the need for a washer; Square neck underneath the head helps self locking
Diameter of the head: 14.3-15mm; Height of the round head: 3.18-3.68mm; Height of the Neck:3.18-3.96mm
Made of 304 stainless steel 18-8 (no coating outside) which is superior to regular steel and any zinc plated fasteners, provides good strength and corrosion resistance in bad environments
| SELLER | SELLER SCORE | AMAZON FULFILLED | PRIME | FREE SHIPPING |
|---|---|---|---|---|
| Discount Distributors LLC | 6.05 | ✅ | ✅ | ✅ |
Thread Diameter 0.250"
Head Diameter 0.594"
Head Height 0.145"
Square Neck Height 0.156" / Square Neck Width 0.26"
18-8 Stainless Steel provides strength and offers good corrosion resistance in many environments.
| SELLER | SELLER SCORE | AMAZON FULFILLED | PRIME | FREE SHIPPING |
|---|---|---|---|---|
| Aoesin | 9.95 | ✅ | ✅ | ✅ |
Standard: ASME/ANSI B18.5
Thread Size: 3/8 inch; Thread Pitch: 16 threads per inch (TPI)
Head Diameter: 0.782 inch to 0.844 inch; Head Height: 0.188 inch to 0.288 inch
Screw Length (include the square neck): 4 inch
Material: 304 Stainless Steel 18-8 that you will probably see in your pans and cookery tools. It's used for a wide variety of home and commercial applications. Because of its slightly higher strength and wear resistance than type 316, it's also used for nuts, bolts, screws and other fasteners.
| SELLER | SELLER SCORE | AMAZON FULFILLED | PRIME | FREE SHIPPING |
|---|---|---|---|---|
| Amazon.com | 9.68 | ✅ | ✅ | ✅ |
Carriage Bolts are designed to fasten a wooden face to either wood or metal
Flat head provides a semi-flush finish to applications
The heads is designed to eliminate the need for a washer
Square underside of the head is self locking to eliminate the need for a driving tool
Galvanized finish is perfect for rust prevention
| SELLER | SELLER SCORE | AMAZON FULFILLED | PRIME | FREE SHIPPING |
|---|---|---|---|---|
| Amazon.com | 9.68 | ✅ | ✅ | ✅ |
Carriage Bolts are designed to fasten a wooden face to either wood or metal
Flat head provides a semi-flush finish to applications
The heads is designed to eliminate the need for a washer
Square underside of the head is self locking to eliminate the need for a driving tool
Galvanized finish is perfect for rust prevention
| SELLER | SELLER SCORE | AMAZON FULFILLED | PRIME | FREE SHIPPING |
|---|---|---|---|---|
| Amazon.com | 9.68 | ✅ | ✅ | ✅ |
Carriage Bolts are designed to fasten a wooden face to either wood or metal
Flat head provides a semi-flush finish to applications
The heads is designed to eliminate the need for a washer
Square underside of the head is self locking to eliminate the need for a driving tool
Galvanized finish is perfect for rust prevention
| SELLER | SELLER SCORE | AMAZON FULFILLED | PRIME | FREE SHIPPING |
|---|---|---|---|---|
| FASTENER DEPOT, LLC | 9.77 | ❌ | ❌ | ❌ |
Thread Diameter 0.3125"
Head Diameter 0.719"
Head Height 0.176"
Square Neck Height 0.187" / Square Neck Width 0.32"
18-8 Stainless Steel provides strength and offers good corrosion resistance in many environments.
| SELLER | SELLER SCORE | AMAZON FULFILLED | PRIME | FREE SHIPPING |
|---|---|---|---|---|
| Amazon.com | 9.68 | ✅ | ✅ | ✅ |
| SELLER | SELLER SCORE | AMAZON FULFILLED | PRIME | FREE SHIPPING |
|---|---|---|---|---|
| Amazon.com | 9.68 | ✅ | ✅ | ✅ |
Carriage Bolts are designed to fasten a wooden face to either wood or metal
Flat head provides a semi-flush finish to applications
The heads is designed to eliminate the need for a washer
Square underside of the head is self locking to eliminate the need for a driving tool
Galvanized finish is perfect for rust prevention
| SELLER | SELLER SCORE | AMAZON FULFILLED | PRIME | FREE SHIPPING |
|---|---|---|---|---|
| Amazon.com | 9.68 | ✅ | ✅ | ✅ |
Carriage Bolts are designed to fasten a wooden face to either wood or metal
Flat head provides a semi-flush finish to applications
The heads is designed to eliminate the need for a washer
Square underside of the head is self locking to eliminate the need for a driving tool
Galvanized finish is perfect for rust prevention
| SELLER | SELLER SCORE | AMAZON FULFILLED | PRIME | FREE SHIPPING |
|---|---|---|---|---|
| Gatzies | 9.78 | ❌ | ❌ | ❌ |
Carriage Bolts are designed to fasten a wooden face to either wood or metal
Flat head provides a semi-flush finish to applications
The heads is designed to eliminate the need for a washer
Square underside of the head is self locking to eliminate the need for a driving tool
Galvanized finish is perfect for rust prevention
| SELLER | SELLER SCORE | AMAZON FULFILLED | PRIME | FREE SHIPPING |
|---|---|---|---|---|
| Amazon.com | 9.68 | ✅ | ✅ | ✅ |
Carriage Bolts are designed to fasten a wooden face to either wood or metal
Flat head provides a semi-flush finish to applications
The heads is designed to eliminate the need for a washer
Square underside of the head is self locking to eliminate the need for a driving tool
Galvanized finish is perfect for rust prevention
| SELLER | SELLER SCORE | AMAZON FULFILLED | PRIME | FREE SHIPPING |
|---|---|---|---|---|
| Amadeo City | 9.86 | ✅ | ✅ | ✅ |
Product Name: Square Head Bolt; Material: Carbon Steel; Finish: Zinc Plated; Color: Silver Tone; Thread Size: M6 x 20mm / M6 x 0.79"(D*L); Pitch: 1mm
Head Size: 10mm x 10mm x 2mm / 0.39" x 0.39" x 0.08"(L*W*T); Package Content: 20 x Square Head Bolt
Advantage: Square head bolt offers a large bearing area, is made of carbon steel, zinc plated finish to prevent rust, high strength, good wear resistance and good impact resistance, and durable.
Application: Square head bolt can be used for toilet lid installation, and it is also widely used in the assembly and maintenance of machinery, railroad, electrical connections, construction, some assembly required furniture and DIY project. Such as the assembly and fixing of guardrails, home appliances, pipeline installations, equipment, steel-framed houses, etc.
Installation: A wrench/plier is required for installation. Generally, with a nut and a washer to form a fastener device(Not in the package).
| SELLER | SELLER SCORE | AMAZON FULFILLED | PRIME | FREE SHIPPING |
|---|---|---|---|---|
| Amazon.com | 9.68 | ✅ | ✅ | ✅ |
Carriage Bolts are designed to fasten a wooden face to either wood or metal
Flat head provides a semi-flush finish to applications
The heads is designed to eliminate the need for a washer
Square underside of the head is self locking to eliminate the need for a driving tool
Galvanized finish is perfect for rust prevention
| SELLER | SELLER SCORE | AMAZON FULFILLED | PRIME | FREE SHIPPING |
|---|---|---|---|---|
| Amazon.com | 9.68 | ✅ | ✅ | ✅ |
Material: steel
Thread size: 1/2''-13
Length: 2-1/2 inch
Low-Strength Grade A Steel Square Head Bolt, 1/2"-13" Thread Size, 2-1/2" Long (Pack of 5)
| SELLER | SELLER SCORE | AMAZON FULFILLED | PRIME | FREE SHIPPING |
|---|---|---|---|---|
| Amazon.com | 9.68 | ✅ | ✅ | ✅ |
Carriage Bolts are designed to fasten a wooden face to either wood or metal
Flat head provides a semi-flush finish to applications
The heads is designed to eliminate the need for a washer
Square underside of the head is self locking to eliminate the need for a driving tool
Galvanized finish is perfect for rust prevention
| SELLER | SELLER SCORE | AMAZON FULFILLED | PRIME | FREE SHIPPING |
|---|---|---|---|---|
| Amazon.com | 9.68 | ✅ | ✅ | ✅ |
Designed for use in conveyor systems
Large low head provides a flush wide bearing connection in soft materials
Square neck prevents rotation
Machine threads for use with a nut
Plain steel bolts not intended for exterior use
| SELLER | SELLER SCORE | AMAZON FULFILLED | PRIME | FREE SHIPPING |
|---|---|---|---|---|
| Amazon.com | 9.68 | ✅ | ✅ | ✅ |
Carriage Bolts are designed to fasten a wooden face to either wood or metal
Flat head provides a semi-flush finish to applications
The heads is designed to eliminate the need for a washer
Square underside of the head is self locking to eliminate the need for a driving tool
Galvanized finish is perfect for rust prevention
| SELLER | SELLER SCORE | AMAZON FULFILLED | PRIME | FREE SHIPPING |
|---|---|---|---|---|
| FASTENER DEPOT, LLC | 9.76 | ❌ | ❌ | ❌ |
Carriage Bolts are designed to fasten a wooden face to either wood or metal
Flat head provides a semi-flush finish to applications
The heads is designed to eliminate the need for a washer
Square underside of the head is self locking to eliminate the need for a driving tool
Galvanized finish is perfect for rust prevention
| SELLER | SELLER SCORE | AMAZON FULFILLED | PRIME | FREE SHIPPING |
|---|---|---|---|---|
| Amazon.com | 9.68 | ✅ | ✅ | ✅ |
Carriage Bolts are designed to fasten a wooden face to either wood or metal
Flat head provides a semi-flush finish to applications
The heads is designed to eliminate the need for a washer
Square underside of the head is self locking to eliminate the need for a driving tool
Galvanized finish is perfect for rust prevention
Here is the list of top-rated brands that were evaluated by PM.
| Brand | Count |
|---|---|
| Hillman | 22 |
| Uxcell | 4 |
| Fastenere | 2 |
| Aoesin | 1 |
| Bolt Dropper | 1 |
| Eastlo | 1 |
| Hard-To-Find Fastener | 1 |
| Mewudecor | 1 |
| Small Parts | 1 |
| The Hillman Group | 1 |
We've carried out a comprehensive analysis of 1,103 reviews on square head bolts, using our selection criteria to identify the best options in the fasteners. Our findings reveal that most customers typically select square head bolts priced around $31.77, with top brands including hard-to-find fastener and small parts and uxcell
Our team of expert editors reviewed these high-quality items and handpicked the top 21 square head bolts for your consideration. We've also done extensive research on numerous sellers, identifying the best ones in the fasteners category. These include and amazon.com and amadeo city .
We are dedicated to assisting our users in finding the right bolts Products based on their needs, saving them considerable time when choosing which square head bolts to buy. We take pride in the number of satisfied users we've helped through our thorough and insightful reviews.
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