It depends on the diameter of your bit and how deep each hole is - I have drilled hundreds of holes with my half inch SDS bit without any sign of weakening (though moderate wear on the tip is apparent).

How long do masonry bits last?

How long will bits last? Speed and bit life depend on several factors, including the type of aggregate, age of the concrete, type and sharpness of the bit and the amount of steel or rebar in the concrete. Generally, you can expect to drill between 150 and 250 holes with each bit.

How do you know if a masonry drill bit is dull?

After the hole has been started do not attempt to realign an off-center hole by exerting undue side pressure on the carbide tipped drill bits. This may cause the bit to break. If the carbide tipped drill bits aren't cutting as fast as when new, this is a good indication that carbide-tip is dull.