Looking for a basin integrated with a toilet tank? This guide highlights top basin-and-toilet units that save space, reduce water use, and suit compact bathrooms, RVs, or outdoor setups. Each product is chosen for distinct buyer needs—from space-saving designs to environmental savings and portable options. Below is a quick table of the featured picks to aid side-by-side comparison.
| Product | Brand | Best for | Dimensions / Fit | Notes |
|---|---|---|---|---|
| Sink Twice Adaptable Toilet Tank Sink | SinkTwice | Most toilets with unknown dimensions | Best for 16.8” to 20” tanks | Built-in spout; water recycling for flush |
| Simple Project 3-IN-1 Modern 17 Inch ADATall Toilet with Sink | Simple Project | Small baths and apartments needing 3-in-1 | 17″ tall; compatible with compact spaces | Includes faucet; space-saving design |
| Outvita Portable Sink and Toilet Combo | Outvita | Outdoor, camping, RVs, or travel boats | 5-gallon fresh water; portable and pump-assisted | Includes soap dispenser and towel rack |
| Sinkology SinkPositive GreenFlow Toilet Tank Sink | Sinkology | Tiny homes, RVs, eco-conscious setups | Easy retrofit; fits standard tanks | Fresh water wash with tank integration |
| SinkTwice for toilet tanks 15.25″ – 16.8″ wide | SinkTwice | Tanks 14″ to 16.8″ with lid off | 15.25″–16.8″ wide | Touchless handwashing with foam soap platform |
The following sections detail five selected products. Each entry notes who it’s best for, why it was chosen, and any practical caveat. Use this as a buying-start guide to match your space, water-use goals, and budget with a compatible basin-and-toilet unit.
Sink Twice Adaptable Toilet Tank Sink
The Sink Twice Adaptable Toilet Tank Sink is designed to retrofit a wide range of gravity-fed toilets with a built-in sink on the tank lid. It aims to conserve water by redirecting refill water through a spout for handwashing before a second flush. Best for households without fixed toilet dimensions or those seeking a universal fit. Caution: verify compatibility with your toilet model and tank height before installation.
Simple Project 3-IN-1 Modern ADATall Toilet With Sink
This 3-in-1 setup combines a toilet, a top sink, and a faucet into one compact unit. It’s ideal for small bathrooms, guest rooms, and apartments where floor space is scarce. It supports a water-saving workflow by using toilet tank water for subsequent flushes. Caution: 1.28 GPF single flush capability may vary by model; ensure your plumbing makes sense for reuse cycles.
Outvita Portable Sink and Toilet Combo
The Outvita combo targets outdoor and mobile use. It features a 5-gallon fresh-water reservoir, a portable pump flush, a 3L soap dispenser, and a towel rack. Best for camping, RV trips, boats, and temporary setups where water access is limited. Limitation: designed for portable use; not a permanent indoor retrofit in most homes.
Sinkology SinkPositive GreenFlow Toilet Tank Sink
The SinkPositive GreenFlow retrofit focuses on space-saving and ease of installation. It provides a fresh-water wash each time you use the sink and is designed to easily replace a standard toilet tank cover. Best for tiny homes and eco-conscious users who want a straightforward retrofit without plumbing changes. Caution: confirm your tank size and lid compatibility before purchase.
SinkTwice for Toilet Tanks 15.25″ – 16.8″ Wide
This model fits tanks ranging from 14″ to 16.8″ with the lid off. It features a touchless handwashing platform using foam soap. Best for owners who want a hygienic, low-contact solution with a compact footprint. Choose this if your tank measures within the specified width; avoid if your tank exceeds 16.8″ or uses a non-standard top lid.
Buying Guide: Key Purchase Considerations
- Space and fit: Measure tank width, lid clearance, and available floor area. Some units specify exact tank widths and height compatibility.
- Water usage and reuse: Consider whether the unit reuses water for flushing and how much you can reduce overall consumption in your bathroom.
- Installation and retrofit needs: Some products require no plumbing changes, while others may need simple modifications or compatibility checks with gravity-fed toilets.
- Portability vs. permanence: Portable outdoor kits are ideal for campsites, whereas retrofits suit fixed indoor bathrooms.
- Maintenance and cleaning: Look for designs with easy-to-clean surfaces and accessible spouts or soap dispensers.
Frequently Asked Questions
- What is a basin integrated with a toilet tank?
It is a toilet top sink or tank-sink design that directs toilet refill water into a sink for handwashing, reducing water waste. - Who should consider a toilet tank sink retrofit?
Homeowners in small spaces, eco-conscious users, and those managing water bills may benefit most. - Are these products easy to install?
Many are designed for retrofit with minimal plumbing changes, but always verify compatibility with your toilet model. - Can these systems fit RVs or outdoor setups?
Yes; several models offer portable or compact designs suitable for camping or boats. - Do these units affect toilet flushing performance?
Some designs reuse tank refill water for flushing, which can affect flush timing or water pressure depending on the model. - What maintenance should I expect?
Regular cleaning of the sink and faucet area, plus checking seals and fittings for leaks, helps maintain performance.