Drill vs Impact Drill: Hammer Action Is the Key Difference

A regular drill rotates the bit. An impact drill—when the term means a hammer or percussion drill—adds rapid forward-and-back blows for masonry drilling. Switch that hammer action off, and it can drill wood, metal and plastic in the same rotation-only mode as a regular drill. Bosch’s drill/hammer-drill manual specifies those separate modes.

The naming needs care: an impact driver is a different tool, delivering rotational impulses mainly to drive fasteners. It is not another name for a masonry hammer drill. ToolGuyd’s mechanism comparison explains the distinction.

Identify the tool before comparing it

Do not buy from the word impact alone. For example, Bosch calls its UniversalImpact 18V-60 a “cordless impact drill,” but it has a 13-mm metal chuck, torque settings and an impact-drilling mode: it is a drill with a masonry function, not a hex-holder impact driver. Bosch’s product description makes that configuration clear.

Tool	What the mechanism does	Main reason to choose it
Regular drill or drill/driver	Rotates the bit without hammering	General holes; controlled screwdriving if equipped with a clutch
Hammer/percussion drill, sometimes sold as an impact drill	Rotates the bit and adds blows along its length in hammer mode	Masonry holes, plus ordinary drilling with hammer mode off
Impact driver	Adds rotational impulses as resistance rises	Repeated or demanding screwdriving

Drills and hammer drills generally use a chuck that grips different bit-shank sizes. A typical impact driver instead takes 1/4-inch hex accessories. That fit difference matters when choosing bits, not just when choosing the tool. ToolGuyd describes both interfaces; our drill-versus-impact-driver guide covers the fastening choice in more detail.

Match the mode to the material

Wood, metal and plastic: rotation only

Hammer action offers no useful advantage here. Use the correct cutting bit and leave percussion off. A hammer drill can do these jobs, but the extra mode does not automatically make it better at ordinary drilling. Bosch explicitly assigns wood, metal and plastic to drill-only mode in its operating instructions.

For cabinet assembly or other small screws, look for an adjustable screwdriving clutch and controllable low speed. Do not assume every tool labelled “impact drill” includes a screwdriving clutch; check the exact model’s controls.

Brick and concrete: masonry bit plus a suitable hammering tool

A percussion drill is intended for impact drilling in brick, concrete and stone, according to Bosch’s UniversalImpact manual. Pair it with a masonry bit rated for that material and hammer use, and keep the hole within the tool’s stated capacity.

For occasional small masonry holes, that additional mode can justify choosing a hammer drill over a plain drill. For hard concrete, larger holes or sustained concrete drilling, consider a rotary hammer instead. Its percussion mechanism delivers stronger blows than a conventional percussion drill; Bosch recommends that tool category for particularly hard materials in its impact-drill guide.

Ceramic tile: hammer mode off

Do not treat every wall surface as masonry. Hammer action can break tile, so drill the tile with percussion disabled and a bit rated for it. If masonry sits behind the tile, reassess the bit and mode once through the tile rather than hammering through both layers. Bosch’s tile warning specifically cautions against hammer action on bathroom tiles.

Which should you buy?

• Mostly wood, metal, plastic and small screws: choose a drill/driver. Prioritize chuck fit, speed control and a screwdriving clutch over an unused hammer mode.
• Those jobs plus occasional masonry holes: choose a hammer/combi drill with a switchable percussion mode and suitable masonry capacity.
• Mainly long or repeated screws: consider an impact driver as a companion to the drill, not a replacement for its masonry function.
• Regular concrete work: compare rotary hammers rather than assuming a higher-torque drill solves the problem.

Before wall drilling, check for concealed wiring and pipes, as advised in Bosch’s safety guidance. Wear eye protection, use hearing protection during impact drilling, and use the auxiliary handle when supplied. Masonry drilling also produces silica-containing dust: follow the tool’s dust-protection instructions, not just its eye and hearing precautions. These warnings appear in Bosch’s drill manual.