When toilet replacement is the right answer
Toilet replacement is appropriate when: (1) the porcelain is cracked (any crack leaks eventually, repair isn't safe long-term); (2) the toilet uses 1.6+ GPF and water bill matters (modern 1.28 GPF or lower units pay back the upgrade in 5–7 years); (3) repeated clogging despite snaking and proper use (the trapway may be permanently scaled); (4) the seat or rim has staining that won't clean (porcelain glaze is damaged); (5) aesthetic upgrade is part of a bathroom remodel; (6) accessibility need (switching to comfort height).
Toilet replacement is NOT needed for: a slow refill (replace the fill valve, $15–$25 in parts), a leaky tank (replace the flapper, $8–$15), a wobbling toilet (re-set the wax ring and tighten bolts), or a non-functional flush handle (replace the chain or handle, $5–$10). Most "the toilet is broken" complaints are actually broken components within the toilet, not the toilet itself.
Pre-replacement checklist
- Measure the rough-in of your existing toilet (standard 12-inch, less commonly 10-inch or 14-inch). Buy a replacement matching the rough-in.
- Decide on bowl shape — elongated or round-front. Most buyers stick with the same shape as the existing toilet.
- Decide on seat height — comfort height (17–19 inches) or standard (15 inches). If your current toilet feels uncomfortable to sit on, this is the time to upgrade.
- Buy the supply line and wax ring — most new toilets don't include them. A braided stainless steel supply line is $8–$15. A wax ring is $4–$8.
- Buy new closet bolts if the existing ones are corroded — they're often included with the new toilet, but inspect them first.
- Schedule disposal — most municipal trash pickup will take an old toilet but require it to be set out separately or with a tag. Some areas require a bulk-item pickup appointment. Check before removal.
Step 1 — Shut off water and drain the old toilet
Locate the shut-off valve behind/beside the toilet and turn it clockwise to shut. Flush the toilet to drain the tank. Hold the flush handle for 10–15 seconds to drain as much bowl water as possible. Use a sponge or wet-dry vacuum to remove all remaining water from the tank and bowl. The cleaner the toilet is when you remove it, the easier the disposal.
Step 2 — Disconnect water supply line
Use an adjustable wrench to loosen the nut at the bottom of the tank where the supply line connects. Have a bucket ready — some water will drain. Remove the supply line entirely; don't reuse old supply lines (they're cheap and degrade over time).
Step 3 — Remove the old toilet
Remove the decorative caps over the closet bolts at the base. Loosen and remove the nuts. Rock the toilet gently side to side to break the wax ring seal. Lift straight up. If it's a two-piece toilet, you can remove the tank first (unscrew the tank bolts and lift the tank off the bowl) to lighten the lift — this is usually easier than lifting the whole assembly.
Place the old toilet on towels or directly in the disposal area. Plug the open drain in the floor with a rag or temporary cap to prevent sewer gas from coming up.
Step 4 — Inspect and prep the closet flange
Scrape off all old wax ring residue with a putty knife. Inspect the flange:
- Cracked or broken: replace it. Use a repair ring or a full flange replacement. Don't install a new toilet over a broken flange — it will leak.
- Below the finished floor: use a flange extender (often called a "spacer" or "repair flange") to bring it flush with the floor.
- Above the floor by 1/4" or less: usually fine, but the toilet base may not sit completely flush. Shim with plastic toilet shims after install.
- Significantly above the floor (1/4"+) or unstable: re-set or replace before continuing.
Step 5 — Install new closet bolts and wax ring
Slide new closet bolts into the flange slots. Place the wax ring on the flange (the flat side down, the tapered side up). Center it over the drain opening.
Step 6 — Set the new toilet
Lift the new toilet over the flange (with a helper for one-piece models). Align the holes in the toilet base with the closet bolts. Lower straight down without twisting or rocking. Sit briefly on the toilet to compress the wax ring.
Step 7 — Tighten closet bolts evenly
Place washers and nuts on the bolts. Tighten alternately, side to side, until snug. Don't over-tighten — porcelain cracks. Cut off the excess bolt length with a hacksaw or bolt cutter, leaving about 1/2" above the nut. Replace the decorative caps.
Step 8 — Connect supply line and turn water back on
Attach the new supply line — finger-tight plus 1/4 turn with a wrench. Turn the shut-off valve counterclockwise to fill the tank. Watch for any leaks.
Step 9 — Test thoroughly
Flush 5+ times. Inspect for:
- Water seepage around the base (indicates wax ring leak — re-set required)
- Drips at the supply line connections
- Tank-to-bowl leaks on two-piece models (tighten tank bolts or replace tank-to-bowl gasket)
- Slow tank refill (fill valve adjustment may be needed)
If everything is dry and the flush is strong, you're done. Optional finishing: apply a small bead of bathroom silicone around the base where it meets the floor, leaving a 1–2 inch gap at the back as an escape route for any future leak.
Disposing of the old toilet
Most municipal trash pickup will accept toilets but with specific requirements — usually a bulk-item tag ($5–$15) or a scheduled pickup appointment. Some recycling centers accept porcelain for ceramic recycling (rare but worth checking). Charity organizations don't accept used toilets (sanitary concerns).
If you broke the porcelain during removal, bag the shards in heavy-duty contractor bags and follow your municipal sharps-disposal rules. Some areas treat broken porcelain as construction debris.
When to call a plumber instead
Hire a plumber if: (1) the closet flange is damaged and needs replacement, (2) the toilet is one-piece and you can't arrange the lift, (3) there's previous floor water damage you can see around the base, (4) the bathroom layout requires moving the rough-in (not really replacement, that's renovation), (5) you're not confident in your ability to detect a slow leak before it damages the floor. Plumber cost for a straightforward toilet replacement: $200–$400 plus the cost of the toilet itself.