A slow-flushing toilet is usually fixable with a few common steps. Here’s a practical, step-by-step guide you can follow, plus a few quick checks to help diagnose the cause. What to try first (simple fixes)

• Check and adjust the toilet tank water level
  • Remove the tank lid and confirm the water level is about 1/2 inch below the top of the overflow tube.
  • If low, adjust the fill valve to raise the level, then flush to test.
• Inspect the flush mechanism
  • Look at the flapper or canister seal. If it doesn’t lift fully or seals poorly, replace the flapper or adjust the chain length so there’s just enough slack (about 1–2 links of play).
  • Ensure the handle/chain isn’t sticking or obstructed.
• Clear the rim and jet holes
  • Check and clean the tiny holes around the rim and the jet holes in the toilet bowl. Mineral buildup can throttle flow; use a small brush and, if needed, a mild vinegar soak to loosen deposits.
• Plunge the toilet
  • Use a flange plunger with a proper seal. Give several firm, vertical plunges to help dislodge minor clogs. If the water remains unusually low or sluggish, you may have a partial clog deeper in the drain.
• Inspect the waste vent
  • A blocked vent can cause slow drainage. If possible, climb to the roof (or access where safe) and inspect/clear the vent stack with a small brush or auger. If you’re not comfortable, call a professional.

More involved checks (if the simple steps don’t fix it)

• Check the fill valve and refilling
  • A worn or clogged fill valve can limit water entering the tank, reducing the flush power. Replacing the fill valve is a common and affordable fix.
• Look for mineral buildup inside the valve or passages
  • Mineral scale can restrict flow. Soak removable parts (like the fill valve cap or flapper) in vinegar to dissolve buildup, then reinstall.
• Consider a partial or full drain-and-clean
  • If the drain or trap is partially blocked, a professional may need to snake the line. Avoid aggressive methods that could damage porcelain or plumbing.

When to call a plumber

• If you’ve tried the above and the toilet is still slow to flush, or if there are signs of a more serious clog, clogged vent, or persistent running after adjustments, it’s wise to get a plumber to inspect.

Safety and maintenance tips

• Turn off the water supply before removing parts, and have a bucket or towel handy to catch spills.
• Regular maintenance: clean the rim and jet holes annually, inspect the flapper and fill valve every 1–2 years, and avoid using harsh chemicals that can degrade gaskets and seals.

If you’d like, tell me your toilet brand or model, what you’ve already tried, and describes any unusual sounds or water behavior, and I can tailor the steps to your setup.