In most cases, yes, but it depends on your benchtop material. Undermount basins are fixed to the underside of the benchtop, so they generally need a stone, solid surface or stone composite benchtop. Laminate benchtops are not usually suitable, since the exposed cut edge is prone to water damage without the lip that an above-mount sink provides.
If your benchtop is laminate, we can talk you through options, including replacing the benchtop section or choosing a different sink style that still gives a similar clean look. Cutout size and shape will also usually differ from your existing above-mount sink, so this is something we always confirm as part of the fixed-price quote before ordering anything.