Best Drill Bits for Stainless Steel of 2026

The first thing we check in a stainless set is whether the common sizes are duplicated. Bosch's CO21B gives you 21 pieces from 1/16 to 1/2 inch, with two each of 1/16, 5/64, 1/8, 3/16, and 1/4 inch. Those are the sizes that wear out first, and having a spare in the case is more useful than another oddball diameter. The bits are M42 cobalt with 8% cobalt, not a titanium coating over ordinary steel.

The three-flat shanks are the detail that makes this set feel like a working set. They hold in a keyed chuck when you lean into stainless, and the 135-degree split point starts without a punch on clean metal. We also appreciate the thick web-helix design, which gives the bits a steadier feel in tough cuts. M42 is hard and heat-resistant, but it is also brittle; keep the drill straight, use cutting oil, and don't let the bit rub.

There are gaps. The range jumps from 3/8 to 1/2 inch without a 7/16-inch bit, and the plastic case is a simple box rather than a shop-grade index. If your work is mostly 1/4-inch and smaller, neither matters much. If you regularly need 7/16, you'll be buying it separately.

What earns it the top spot is the combination of range and duplicates. It covers the sizes a home shop actually uses, and it keeps you working when the first 1/8-inch bit dulls. That practical coverage is the reason to choose it over a set with more pieces but only one of each size.

A twelve-pack of the same 1/8-inch bit looks like overkill until you're drilling a run of rivet holes. That is the job this set is built for: one size, repeated, so a dull or snapped bit doesn't stop the work. The bits are M35 cobalt with 5% cobalt, a 135-degree split point, a 1-5/8-inch flute, and a 2-3/4-inch overall length. We like the narrow focus because it solves a real problem instead of padding an index.

The 1/8-inch size is the workhorse for pilot holes, pop rivets, and small brackets. In stainless, the bit still needs low speed and oil; the cobalt helps with heat, but it doesn't make a small bit immune to side load. We treat the pack as a consumable set: when one starts to slow down, swap it and keep going.

The case is basic, but the spare bits are the feature. The first bit is still in the drill when the next one is already in the case. For a cabinet shop, a race car, or a homeowner with a long list of 1/8-inch holes, that is the useful part.

The pilot point is the reason to look at this DEWALT set. A small centering tip starts the hole before the full cutting edge engages, which is handy on sheet metal and rivets where a standard bit wants to walk. The 14-piece set is cobalt alloy steel with a 135-degree cutting angle.

On stainless, the pilot point helps at the start, but it doesn't change the rules once the full diameter is cutting. Keep the speed low, use oil, and let the bit cut instead of rubbing. The set is at its best on light sheet, brackets, and mixed metalwork; it is not the set we choose for a long run of thick plate.

The bits are hard, and hard bits can snap if you side-load them. We treat that as the price of cobalt: it holds an edge in stainless, but it is less forgiving than a softer general-purpose bit. The connectable case is easy to see into and the bits come out without a fight, which matters when you're switching sizes.

What makes it a runner-up is the pilot point, not the piece count. If your work is rivets and light sheet, the point saves you a punch and a wobble. The pilot point is the feature that earns its place; the rest is a solid cobalt set, not a full shop index.

The 15-piece COMOWARE set is the budget route into cobalt. It runs from 1/16 to 3/8 inch in common steps, uses M35 steel with 5% cobalt, and has a 135-degree split point. For a homeowner who drills stainless a few times a year, that is enough range for pilot holes, clearance holes, and small brackets.

What makes it useful is the size ladder. It covers the sizes you reach for without making you buy a 29-piece index, and the bits cut well in light stainless and mild steel. We also noticed the M35 alloy is a step below M42 in heat resistance, so it rewards a slower, wetter drilling technique.

The case is the part we minded. The rack doesn't hold the bits securely and the lid is fussy to close, so the set is happier on a shelf than in a portable box. If you keep it open in a drawer, that's a minor annoyance. If you carry it to jobs, plan on a different case.

For a light stainless workload, the size ladder is the right compromise. It covers the common sizes without making you pay for a full index, and it leaves room in the budget for cutting fluid and a spare of the size you use most.

One bit, fifteen steps, 4 to 32 mm: the STROTON step bit is for the job where you don't know the final hole size until you get there. We reach for a step bit when we're enlarging a hole in a panel, fitting a connector, or opening up a bracket that already has a starter hole. The M35 cobalt and 5% cobalt content give it a better chance in stainless than a titanium-coated step bit.

The range is the appeal: 4, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24, 26, 28, 30, and 32 mm. That covers a lot of conduit and panel work, and it saves swapping five twist bits. The catch is that a step bit cuts on a taper, so you have to keep the drill perpendicular and let each step finish before pushing to the next.

We noted the single-flute design clears chips well but can grab if you rush it. Use oil, keep the speed down, and let the tool do the work. For enlarging stainless, though, it's the most efficient tool here.

The 29-piece Drill America set is the most complete index here: 1/16 to 1/2 inch in 1/64-inch increments, M35 cobalt, 135-degree split point, gold oxide finish, and ANSI specification. If you've ever needed a 7/64-inch bit and had to jump to 1/8, you know why the in-between sizes matter.

The value is in the steps between the common sizes. A full 1/64 index lets you open a hole gradually instead of forcing a bigger bit, which is exactly how you avoid work-hardening stainless. The round case keeps the set organized and the bits are easy to read by size.

We found the bits sharp and well made, and they cut through mild steel and stainless without the drama of a hardware-store set. The trade-off is weight: this is a bench set, not a portable kit. The 2.2-pound set is fine in a drawer and annoying in a tool bag.

This is the set for a shop with a drill press and a drawer for a full index. For occasional home use, the Bosch is the easier set to live with; for precise, repeat metalwork, the extra sizes are the reason to step up. The one-bit-per-size format is the catch when a common size dulls.

Ten identical 1/4-inch bits is a strange-looking purchase until you're drilling a bracket run or a fixture plate. The amoolo pack is M35 cobalt with 5% cobalt, a 1/4-inch diameter, a 135-degree split point, and a 90-day warranty. It is a production pack, not a starter set.

The single-size format makes sense for the same reason the Drill Hulk pack does: the common size is the one that wears out, and buying ten means you don't stop to reorder. We like that the bits are uncoated, so there's no coating to wear through before the edge dulls. The case is basic, but it keeps the spares together.

We found the bits cut cleanly in stainless when we kept the speed down and used oil, and the 135-degree point started without a punch. For a specific 1/4-inch job, it's the practical buy, especially if you already know that size is the one you burn through.

A single 1/4-inch bit with a 4-inch length is a problem-solver, not a set. The Bosch CO2143B is M42 cobalt with 8% cobalt and a 135-degree split point, so it belongs to the same family as our top pick. The cutting diameter is 1/4 inch, and the bit is made for stainless, cast iron, titanium, light-gauge metal, and aluminum.

The extra length is the reason to look at it. A standard jobber bit can run out of reach in a bracket, a panel, or an assembly where the chuck fouls the surface. The 4-inch bit gets through those spots without an extension, and the split point still starts without a punch.

We treat it as a replacement for the size that walks away or dulls first. It's a known quantity in stainless, and the M42 alloy gives it more heat resistance than a basic HSS bit. The trade-off is that you're paying for one bit and a small sleeve rather than a range; that only makes sense if the rest of your set is already covered.

The 4-inch length is what makes it worth keeping separate from the set. It saves a trip when a deep 1/4-inch hole stops you, and the extra reach is the reason it stays in the drawer even when the full index is close by.