Most toilets use either a side entry or bottom entry fill valve. In many modern bathrooms, especially in the UK and parts of Europe, the bottom entry fill valve for toilets is the standard choice. It connects at the base of the toilet tank, making it less visible, quieter, and more space-efficient. If your bottom entry fill valve is leaking, noisy, or failing to refill the tank properly, it may be time for a replacement. In this guide, we’ll explain what makes bottom entry valves unique, what to look for when buying one, and review the best models available today.
What Is a Bottom Entry Fill Valve?
A bottom entry fill valve connects at the base of the toilet tank rather than the side. The water inlet pipe comes up from the floor or wall, and the valve sits vertically inside the tank with a float that controls the shut-off point. This design is often preferred for its sleek look and quieter operation.
Benefits include:
- Quieter operation – Less splash and turbulence compared to side entry valves.
- Cleaner appearance – Plumbing is hidden below the tank.
- Compact design – Ideal for toilets installed in tight spaces.
- Modern compatibility – Common in newer one piece and dual flush toilets.
Buyer’s Guide: How to Choose a Bottom Entry Fill Valve
Before purchasing a replacement, consider these important features:
- Adjustable height – Choose a valve that can be adjusted to fit different tank sizes.
- Noise level – Premium valves include noise-reducing features for near-silent refilling.
- Material – Brass shank models offer durability; plastic is more affordable.
- Float type – Modern compact floats take up less space than older ballcocks.
- Compatibility – Check your toilet model (one piece, dual flush, compact, etc.) to ensure proper fit.
Top Bottom Entry Fill Valves for Toilets
Here are three of the best-rated bottom entry fill valves you can buy today:
Fluidmaster 400UK Bottom Entry Fill Valve
Best Overall
This UK-specific model from Fluidmaster is a reliable choice for bottom entry toilets. It’s adjustable, quiet, and built for long-lasting performance.
- Adjustable height for universal fit
- Quiet refill operation
- Trusted Fluidmaster design
Pros: Easy to install, reliable, widely compatible
Cons: Some users report needing adjustments for certain tanks
Verdict: A top universal choice for most bottom entry toilets. Check price here.
Dudley Hydroflo Bottom Entry Fill Valve
Best Premium
The Dudley Hydroflo is a UK-made premium bottom entry fill valve known for its quiet operation and durability.
- Compact float design
- Adjustable water level
- Available in brass or plastic shank versions
Pros: Very quiet, long-lasting, high-quality build
Cons: Higher cost than standard valves
Verdict: Best premium option for lasting performance. See it on Amazon.
Siamp 99T Bottom Entry Fill Valve
Best Budget
The Siamp 99T is a compact, affordable bottom entry fill valve designed for modern cisterns.
- Simple, compact design
- Quick refill function
- Fits most cisterns
Pros: Affordable, easy to fit, dependable
Cons: Not as durable as premium valves
Verdict: Great budget-friendly choice. View today’s price.
Comparison Table
| Product | Best For | Adjustable Height | Material Options | Price Link |
|---|---|---|---|---|
| Fluidmaster 400UK | Overall reliability | Yes | Plastic | View Price |
| Dudley Hydroflo | Premium durability | Yes | Brass or plastic | View Price |
| Siamp 99T | Budget-friendly | Fixed | Plastic | View Price |
FAQ
Are bottom entry fill valves better than side entry?
Both work well, but bottom entry valves are usually quieter and give a cleaner look since the pipe is hidden.
How do I know if I need a bottom entry valve?
Check where your toilet’s water supply connects. If it connects at the base of the tank, you need a bottom entry fill valve.
Can I install a bottom entry fill valve myself?
Yes. Most are DIY-friendly and can be installed in under 30 minutes with a wrench and sponge to remove excess tank water.
How long do bottom entry fill valves last?
On average, 5–7 years. Hard water may shorten lifespan, but premium brass-shank versions last longer.
Do bottom entry valves fit all toilets?
Most modern replacements are universal and adjustable, but always check dimensions against your toilet model.
Conclusion & Call-to-Action
Choosing the right bottom entry fill valve for your toilet restores quiet, efficient refilling and prevents leaks or wasted water. For universal compatibility, the Fluidmaster 400UK is the best all-around choice. If you want a premium, long-lasting option, the Dudley Hydroflo is hard to beat. For budget-conscious buyers, the Siamp 99T offers solid performance at an affordable price.
Order your bottom entry fill valve today and bring your toilet back to reliable, quiet operation.