Why Does My Tub Drain Very Slowly While the Sink In the Same Bathroom Works Fine?
The tub drains slowly, sometimes to the point of leaving a puddle that takes several minutes to disappear, while the sink in the same bathroom drains normally with no issue.
Why this contrast is actually good news
If the problem came from the main drain or plumbing shared by both fixtures, the sink would likely be affected too, at least partially. The fact that only the tub is affected almost always indicates a blockage localized specifically in the tub's drain, rather than a wider, more costly problem.
The most common cause of a slow-draining tub
Hair, combined with soap and other residue, accumulates in a tub drain disproportionately compared to a sink, due to regular use for washing hair and body. This buildup generally forms around or just below the stopper, creating a partial blockage that slows drainage without fully stopping it.
How to confirm this likely cause
| Sign | What it confirms |
|---|---|
| Gradual slowdown over several weeks or months | Progressive buildup typical of hair and residue |
| A slight smell accompanying the slowdown | Decomposing organic matter in the drain |
| The stopper itself appears surrounded by visible residue | Direct visual confirmation of the likely cause |
How to unclog this type of blockage yourself
A tool specifically designed to remove hair (a flexible rod with hooks), inserted directly into the drain, often pulls out a surprising amount of buildup in a single attempt. Removing the stopper or grate for direct cleaning, if the mechanism allows it, also gives direct access to the most surface-level buildup without a specialized tool.
When this basic cleaning isn't enough
If the slowdown persists despite removing the visible buildup, the blockage could be deeper in the drain than a hair-removal tool can reach, requiring a longer plumbing snake or a professional's intervention for a more thorough drain cleaning.
Frequently asked questions
Does a chemical drain cleaner work for this type of clog?+
Partially for light buildup, but a physical hair-removal tool generally remains more effective for this specific type of clog.
How often should I preventively clean the tub drain?+
About every 2-3 months for regular use, which prevents the significant buildup that causes a noticeable slowdown.
Why does the tub drain accumulate more hair than the sink's?+
Use for washing hair and the whole body generates far more residue than a sink used mainly for washing hands or the face.
Does a hair-catching drain mat help with this problem?+
Yes, a grate or mat designed to catch hair before it reaches the drain considerably reduces how often this type of clog occurs.
Get a free quote
More to know before your project.
By Julien Fortin — RBQ-licensed plumber, 10 years of experience in residential plumbing
Updated on July 22, 2026