To replace caulk around a sink, remove the old bead completely, clean and dry the seam, and apply a fresh bead of the right caulk for the surfaces around your sink. A quick touch-up usually won’t hold if the old caulk is cracked, lifting, moldy, or pulling away from the sink or countertop. This guide covers the joint where the sink meets the countertop or backsplash, which is the most common place homeowners need to renew the seal.
Check the finished seal
Once the caulk has cured, inspect the whole seam in good light. You should see a continuous line with no gaps, pinholes, lifted edges, or thin spots where the sink meets the counter or backsplash. The bead should look even in width and should be attached on both sides of the joint.
Run a careful visual check around corners, faucet cutouts, and tight bends, because those areas are easy to miss. If you see a break or a section that separated before curing, cut out that part and reapply it rather than trying to smear more caulk over a bad spot.
A finished seam is doing its job when it looks clean and stays firmly bonded all the way around the sink.