Clean and wash the entire yacht thoroughly
Remove all food, perishables, and personal items
Empty and clean refrigerators, freezers, and lockers
Drain and flush all freshwater tanks, lines, and heaters
Add marine-grade antifreeze to plumbing systems as needed
Winterize engines according to manufacturer instructions
Change engine oil and filters
Replace fuel filters and treat fuel with stabilizer
Fill fuel tanks to reduce condensation
Drain and winterize generators
Service and winterize the watermaker if installed
Drain and protect bilge areas
Remove batteries or keep them on a proper maintainer
Disconnect and store electronics if appropriate
Inspect and protect electrical connections from moisture
Remove sails, canvas, and loose gear
Clean, dry, and store cushions and bedding
Lubricate moving parts, hinges, and fittings
Close and secure all seacocks and valves
Check hoses, clamps, and through-hulls for wear
Protect metal surfaces from corrosion
Cover the yacht with a proper winter cover or shrink wrap
Ensure ventilation to prevent mold and mildew
Secure the vessel against storms, snow, and ice
Check mooring lines, dock lines, and fenders regularly
Inspect the yacht periodically throughout winter
Follow all manufacturer and yard recommendations