I’ve had ants in my home at various times (including the new home we’ve moved into) and I’ve tried all of the various grocery store solutions like Raid and Combat discs (aside, it just struck me how manufacturers like to name their products in such a way as to make controlling ants sound like a full-on war). None of those things ever really worked well for me. What works amazingly well is this simple little recipe:
1.5 cups water
1/2 cup sugar
2 tsp boric acid (available in the pharmacy section; poisonous if taken internally or inhaled)
Bring to boil. Let cool. Pour liquid into bottle caps and place bottle caps in the path of the ants. Typically, the sugar will attract zillions of ants and the problem will appear to get much, much worse for a day or two. Then you will find lots of dead ants to wipe up. Then no more ants. Has worked every time that I’ve used it.
Make sure that if you end up with extra liquid and you store it, that you clearly label it as poison. I use my Brother label maker on the largest font and put skull and bones icons all over it.