How Much Does It Cost to Add a Half Bathroom? [2025 Data]

Adding a half bathroom costs an average of $6,500, though costs go from as low as $3,800 to as high as $25,000. This comes out to about $230 to $550 per square foot to add a new half bathroom, depending on whether it’s a conversion or an addition. While this may seem steep, remember that most home additions add value to your home. Plus, adding a half bathroom adds extra convenience, especially for large households. 

The budget for your new bathroom will have to include hiring different professionals, permits, prep work, and more. Here’s a breakdown of all the cost factors to consider.

Size of Half Bathroom 

Like many home projects, the size of your addition is directly related to your total project cost. However, unlike larger-scale projects like replacing a roof or changing the flooring in your whole house, adding a half bath won’t really benefit from an economy of scale. Ultimately, you’re just not purchasing enough materials to satisfy the requirement for bulk discounts. 

Definition

Here is a look at the average cost to add a half bathroom based on square footage.

Professional Costs

If you don’t choose to go with a home addition company near you, there are various pros you need to hire. Each one has a different rate, and the more specialized they are, the more they will cost. Below is a list of common professionals needed for a half bath addition.

Electrician Costs

Hiring a professional electrician is necessary when you add a half bathroom, since the project involves specific skills that the average homeowner doesn’t have. Common costs include:

• Installing an outlet: $100–$450

• Adding a lightswitch: $60–$300

• Adding a light fixture: $175–$1,100

• Rewiring existing electrical: $625–$2,600

Plumber Costs

You’ll also need a plumber for this project. Make sure they are certified, and double-check where to place the toilet and sink, as these are often expensive to change later. Common costs include:

• Installing a sink: $225–$700

• Replacing pipes: $150–$5,800

• Rough-in plumbing for a bathroom: $3,000–$20,000

Architect Costs

Those without planning skills should hire an architect. Architects often charge a percentage of the total project cost, around 8% to 15%. Hourly rates will amount to $90 to $160 or more. Investing in the cost of hiring an architect is wise to save money down the line, and you may be surprised by a design you wouldn’t have thought of yourself. 

General Contractor Cost 

Working with a general contractor will cost homeowners 15% to 25% of the project cost. While this seems steeper than piecemealing work to separate pros, consider that a general contractor has unilateral control over the entire project. This ensures an even quality of work, and if there are any problems down the line, there is only one pro you need to work with—the general contractor. 

Location of New Half Bathroom 

The location of the new bathroom affects the price because you may have to run new plumbing lines. It will cost around 50% more to build an addition than to convert a space in your basement, garage, hallway, or attic. 

The more plumbing work the room requires, the more it will cost. You can squeeze a small powder room under a staircase or into a laundry room, but you may want to install a larger bathroom in a garage or basement if you have the space available. Remember that larger spaces will cost more. 

Additional Cost Factors

Adding a half bath can have some unwelcome effects on your project’s bottom line. While there are some ways to avoid the two examples below, 90% of homeowners will need to consider them when pricing out—and completing—their half bath addition.  

Demolition and Prep

If you’re taking space off of your living room to accommodate a half bath, you don’t need to do any demo. However, if you decide to significantly alter your home’s layout, expect the price to rise as permits need to be pulled and the cost of planning balloons. You can’t prep much for this job other than removing flooring and existing electrical or plumbing—don’t do this yourself—so you need to hire a pro for anything beyond taping out the area or knocking out some drywall. 

Permits

You’ll likely need a building permit to build a half bathroom. The price of such a permit depends on your municipality, but expect to pay between $125 and $600. If you’re working with a local bathroom remodeler, they will be able to help you through the permit process. However, they will file and secure it themselves as part of your project cost.  

Accessories or Special Features

Half baths have the luxury of being more sparsely furnished than the main bathroom of a house. Many homeowners choose less expensive options because a half bath is often one of convenience, not style. Here are the average costs of some common half-bathroom features.

• Toilet: For most homeowners, toilet installation costs $225–$550, but you’ll spend more on the actual toilet. Plastic toilets cost $50–$200, while ceramic toilets cost $120–$430. Smart and designer toilets can cost more than $800.

• Sink: For most homeowners, sink installation costs $225–$700, but it could surpass $1,200 if you choose a high-end sink. A standard ceramic sink will cost about $100–$550, excluding labor.

• Mirror: Most bathrooms have a mirror above the sink. You can install a mirror that doubles as a medicine cabinet for extra storage, which costs between $90–$300. Certain smart mirror models can cost as much as $800.

• Exhaust fan: Installing a bathroom exhaust fan costs $250–$600. Though most half baths don’t have a shower or tub to make things extra steamy, you’ll still need adequate ventilation.

• Light fixtures: The cost to install a light fixture is anywhere from $175–$1,100, but chandeliers come with the highest price tag. For a small powder room, consider a small ceiling-hung fixture. Sconces around a bathroom mirror are also popular to give you better visibility when styling your hair or washing your hands.

• Tile: Tile installation costs anywhere from $5–$45 per square foot depending on the type of tile. Simple travertine tile costs $3–$9 per square foot on average, while ceramic tile costs $3–$35 depending on whether it’s glazed.

• Flooring: New flooring installation costs $3–$25 per square foot, depending on the type. Laminate flooring is the most affordable at $1–$4 per square foot, excluding labor. Vinyl starts as low as $2 per square foot, and hardwood or tile flooring ranges between  $6–$25 per square foot.

DIY Adding a Half Bathroom vs. Hiring a Pro 

If you choose to DIY a half bath addition, you’ll save around 30% of the total project cost in labor, not taking into account your own time. While this may sound appealing, we recommend combining DIY work with the use of a general contractor, thus lowering the time it takes for the addition. 

You don’t want to attempt any plumbing or electrical work because it can cause serious damage if done incorrectly. However, you can work alongside a general contractor doing some of the more simple work, like tightening screws, painting, or laying down laminate. 

Once you have a proposal for work outlined, discuss with your general contractor what you can do yourself to cut down on costs. 

Tips to Reduce Costs While Adding a Half Bathroom 

When building a half bath, you should focus money-saving efforts on materials, not labor. Some ways you can save are:

• Perform the time-intensive but low-skill labor yourself (like painting). 

• Check salvage stores for used or unused fixtures like sinks and toilets. 

• Sign up for home improvement store discount emails. 

• Talk to your contractor about where you can cut costs in materials. 

• Reuse any old plumbing you might have if it’s still in good working order. 

• Use energy-efficient fixtures (toilets, sinks, lights). 

• Consider budget alternatives to expensive materials like marble and steel. 

Does Adding a Half Bathroom Increase Home Value? 

Adding a half bathroom increases a home’s financial value by about 6%. Depending on the size of your home and the number of bathrooms you already have, this number can fluctuate quite a bit. 

A larger home with five full bathrooms will not see a 6% boost in property value by adding a half bath—more like 2% or even less. Flip the coin and consider a small house with only one bathroom. Adding a half bath to a smaller property can easily increase the home’s value over the 6% average. 

Beyond finances, a half bathroom adds quality of life value to a home. In the above example, a half bathroom in the large house may be used next to a mud room, saving the occupant from having to walk upstairs or across the house. A half bathroom in a small house with one bathroom means there are two available toilets, eliminating the need to take turns for a single bathroom.

Finally, a half-bathroom addition will appeal greatly to buyers looking for more than one toilet and sink in a property and can generate increased interest during a sale.  

How Angi Gets Its Cost Data

Home is the most important place on earth, which is why Angi has helped more than 150 million homeowners transform their houses into homes they adore. To help homeowners with their next project, Angi provides readers with the most accurate cost data and upholds strict editorial standards. We extensively research project costs to develop the pricing data you see, so you can make the best decisions for you and your home. We rely on reputable sources, including the U.S. Bureau of Labor Statistics, academic journals, market studies, and interviews with industry experts—all to ensure our prices reflect real-world projects. 

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