13 Best Drill Bits for Stainless Steel in 2026: Genuine Cobalt That Won't Quit

M42-grade cobalt steel and a split-point tip allow these bits to start on contact in hardened stainless, cast iron, and alloy steel without a center punch. The 3-flat shank locks securely into the chuck, preventing slip on larger sizes. Cutting edges hold up through repeated holes in material that dull standard TiN bits within seconds. Slow speeds and cutting oil produce clean, burr-free results.

This set targets metalworkers and fabricators who drill stainless steel regularly and are comfortable with the discipline of low RPMs, cutting oil, and a drill press or very stable hand. It's not for wood-only shops or those unwilling to adapt technique — lateral force or a drop can snap smaller bits. For that tradeoff, you get a durable, imperial-sizes kit in a well-organized case.

💡 💡 Tip: Always use cutting oil and a drill press when possible; cobalt's heat resistance works best at low RPMs to avoid brittle failure.

Unlike DEWALT's TiN-coated generalist bits, the DWA1240 uses genuine cobalt alloy steel to handle thick stainless and alloy steels that wear down lesser bits. The 14-piece set spans 1/16 to 1/2 inch, making it a practical upgrade for DEWALT loyalists who drill stainless regularly and want the speed of a pilot point that starts cleanly without a center punch. Edge life lags behind the top-performing Bosch CO14 under sustained high-speed use — a tradeoff for the convenience and brand familiarity.

💡 💡 Tip: Use cutting oil and moderate RPMs on stainless to extend edge life.

The 19-piece STROTON set uses M42 8% cobalt to achieve a 68-70 HRC hardness that slices through hardened stainless, tool steel, and titanium alloys. The 135° split point bites immediately and resists walking, while metric sizing from 1 mm to 10 mm in 0.5 mm steps covers the precision needs of European and Asian machinery.

Mechanics and machinists working on metric fasteners and diesel components will appreciate the specific increments and heat tolerance. The sub-2 mm bits, however, are delicate — treat them as consumables and avoid off-center hand drilling to prevent snapping. This set suits users who primarily drill larger metric holes and can handle small bits with care.

💡 💡 Tip: Reserve the sub-2 mm bits for use in a drill press or with a rigid guide — hand-held wobble can snap them.

This 12-pack of identical 1/4-inch M35 cobalt bits is purpose-built for repetitive stainless work. Unlike the top pick that covers a range of sizes with M42 cobalt, Drill Hulk focuses on a single diameter to slash the per-hole cost for trailer builders, automotive shops, and anyone drilling numerous 1/4-inch bolt or rivet holes. The tradeoff: you'll need a separate index for other sizes. But if your job is drilling through 304 stainless plate all day, this bulk pack keeps you in fresh bits at an unbeatable price.

The pilot point tip bites into material without a center punch, minimizing wandering on curved or slick surfaces. Across 21 sizes from 1/16 to 1/2 inch, the hex shanks grip well in chucks, and the TiN coating reduces friction in wood, plastic, and mild steel. When used on stainless steel, the coating wears faster and the bits dull more quickly than genuine cobalt — acceptable for occasional holes, but not for production work.

This set suits homeowners who drill mixed materials and need a single comprehensive kit. Anyone drilling stainless steel regularly should step up to a cobalt set like DEWALT’s M35/M42 option, because the TiN coating cannot be resharpened once worn.

💡 💡 Tip: Use cutting oil and lower RPM when drilling stainless steel to extend bit life and reduce breakage.

Fifteen genuine M35 cobalt 1/4-inch bits offer the lowest per-bit cost for shops that drill repeated holes in stainless steel sheet and tube. The 135-degree split point bites quickly without a center punch, and the 5% cobalt alloy resists heat better than standard high-speed steel. Compared to the top pick's M42 build, these bits trade a bit of edge life for a much larger quantity at a budget-friendly price.

This set is built for fabricators who run through 1/4-inch bits on production stainless assemblies. Longevity under continuous heavy use can vary — occasional snapping has been noted — but the pack assumes some breakage and keeps spares close. Shops that value consumable cost per hole over maximum individual bit life will find the math works.

Sharp and affordable, this 14-piece set excels at wood, plastic, and mild steel. TiN coating handles occasional light-gauge stainless, but edge retention drops under heat and small bits may snap under load. It’s outclassed by the 21-piece set in size range and value, and not a replacement for cobalt bits in regular stainless drilling.

This 10-pack stocks genuine M35 cobalt for small stainless pilot holes at a bargain price. The bits hold an edge through multiple holes with proper oil and feed. The 1/8-inch size snaps easily if hand-drilled or fed unevenly—treat them as consumables. Some packs arrive missing a piece. As an affordable bulk stash where breakage is expected, it works.

The M35 cobalt edges bite into hard metal cleanly when run at low speed with steady pressure and cutting oil. However, high brittleness means they can snap under side load — especially in a hand drill — so true economy depends on careful technique and a drill press.

Quick-change hex shank cuts sheet metal and thin stainless with an impact driver — handy for tight spaces. Their short mechanic length and variable durability, though, restrict them to light-gauge metal; they're not built for deep stainless holes or prolonged hard-metal use.

The Bosch TiN-coated 2-pack stays sharp through light-duty work in thin sheet metal, acrylic, and plastics. Its self-starting point bites without walking. But these bits are limited to 7/64-inch holes in material no thicker than 1/8 inch, and the package contains only two bits. Buyers needing a full set for varied stainless drilling will find this too narrow.

The ZELCAN step bit set drills cleanly in aluminum, thin mild steel, and plastic, with a wide 50-step range and a well-organized case. On stainless steel, the titanium coating breaks down quickly, dulling edges after just a few holes. Electricians and HVAC techs working with enclosures will appreciate it, but anyone drilling stainless steel should look to cobalt bits.

The comprehensive fractional range from 1/16 to 1/2 inch and metal index box appeal to organized tool collectors. For stainless steel, the M35 cobalt edges may struggle with consistency — bits can skate or dull instead of cutting. This set suits occasional light-metal and wood drilling where full size coverage justifies the premium price, not production stainless work.