The single most useful upgrade you can make to your kitchen costs nothing: stop asking one bottle of olive oil to do two different jobs.
A cooking oil lives next to the hob. It gets splashed into pans, poured over roasting trays and used by the glug. It should be decent, honest and affordable, because heat flattens the delicate flavours you pay a premium for. Any reliable mid list oil from our top 33 ranking does this job well.
A finishing oil is different. It goes on after the heat: over salads, soups, grilled fish, good bread, a plate of tomatoes. Here the oil is an ingredient, not a medium, and freshness is everything. This is where a harvest dated, single origin bottle earns its price, because you can actually taste the difference.
The math works out too. A premium bottle used only for finishing lasts months, so the cost per meal is cents. Meanwhile you stop burning ten-dollar flavour in a frying pan.
If you want a starting point for each bottle, our ranking of the 33 best olive oils in the world covers both ends: workhorses in the bottom half, and a clear winner for the raw jobs at the top.