Gather tools and supplies: new toilet seat, adjustable wrench or screwdriver (as needed), putty knife or scraper, cleaning cloth, and toilet-safe cleaner
Turn off water if needed for access, then remove the old seat
Open the lid and locate the mounting bolts at the back of the toilet bowl
Loosen the nuts/bolts holding the seat using an adjustable wrench or screwdriver
If bolts are stuck, apply penetrating lubricant, wait a few minutes, then try again
Remove the old seat and any washers
Scrape off old residue from the mounting holes and clean the area thoroughly
Check the mounting hole spacing on the toilet (commonly standard or elongated) and ensure the new seat matches
Position the new seat over the mounting holes with the hinges aligned
Insert the bolts through the seat and into the mounting holes
Add washers and tighten nuts by hand first to align the seat correctly
Tighten securely without over-tightening to avoid cracking the porcelain
Verify alignment and stability by gently lifting and lowering the seat
Recheck tightness and adjust if the seat shifts
Clean any fingerprints or marks from the toilet and seat
Test the lid and seat for smooth movement and secure attachment