Find out how much paint you’ll need, along with painter costs for your interior painting job by providing the following information.
Trying to figure out how much your painting project will cost? Here’s the good news: calculating the amount of paint needed for your interior painting job is actually much simpler than tackling those tricky edges around window frames.
Keeping up with regular interior painting not only refreshes your space but also protects your walls from deterioration and helps you avoid expensive repairs caused by moisture damage.
To estimate your interior painting costs, you’ll need to start by calculating the square metreage of the room you’re planning to paint. Below are some real-world examples of professional painting costs for different room sizes. Each estimate includes one coat of primer and two coats of paint, plus ceiling coverage and paint for window sills and doors.
Living Room
Bedroom
Bathroom
While you can deduct window areas from these calculations for greater precision, we’ve found it’s often wise to budget for the full room dimensions. This approach gives you a buffer for touch-ups, unexpected challenges, or additional coverage needs—particularly helpful when you’re painting multiple rooms in the same colour and want to ensure you have enough paint on hand.
In most cases, you’ll need two coats of paint plus one coat of primer. That said, the actual number depends on your wall’s current condition and what you’re painting over.
For instance, transforming a dark blue wall into a crisp white will typically require additional coats to achieve full coverage. On the other hand, if you’re simply refreshing your walls with the same existing colour, a single coat might be sufficient.
With countless interior paint options on the market, each brand comes with its own price point and coverage rate (the surface area one litre can cover). You’ll typically find this information on the paint tin itself, or you can ask staff at your local hardware store or consult a professional painter. Our calculator above uses a standard coverage rate of 15m² per litre for all painting estimates.
Here’s what some of Australia’s leading paint brands recommend:
Dulux
As Australia’s most recognized paint brand, Dulux provides the following coverage guidance: One litre of Dulux Wall, Dulux Trim, or Dulux Ceiling paint covers approximately 16m², while one litre of Dulux Primer covers approximately 14m².
For a medium-sized room (up to 4.3m × 4.3m), they recommend 15 litres of paint total, broken down as follows:
At Bunnings, you’ll pay around $218 for 10 litres of Vivid White Low Sheen Wash&Wear Interior Paint, approximately $140 for 5 litres of primer, and $64 for one litre of Aquanamel paint for doors and trims.
Taubmans
According to Taubmans, that same room size (4.3m × 4.3m) with one window and one door requires approximately 12 litres of paint for two coats on walls and trims. This breaks down to:
At Bunnings, 12 litres of Taubmans Endure Interior Paint costs approximately $260.
British Paints
British Paints recommends 9 litres for a 4.3m × 4.3m room, plus an additional 5 litres for the ceiling (based on two coats).
Depending on your specific British Paints selection, expect to pay around $260 at retailers like Bunnings. The total may increase if you add primer or specialty gloss paints for trims.
Pro tip: Modern interior painting techniques focus on efficient workflows and comprehensive protection of your furnishings, minimizing disruption to your daily routine.
It’s probably not surprising that when it comes to interior house painting, the cost varies depending on the size of your house and how much of it you’re painting.
But, if you’re going with a professional painter (which you should if you want it looking top notch), the cost — according to Alexander Berry, from R.J & A.L Berry Painting in Piara Waters, Western Australia — painting cost per square metre is around $60 – $100 per m2. For Alexander, this rate includes the cost of the paint itself, with paint for your doors and window frames too.
Depending on the tradie and scope of work, this cost could cover things such as:
Prep work such as sanding and filling cracks
Priming the surface
Two coats
Doors, windows and trims
Materials and paint
Tools
Labour/wages for your painter
Always check what’s included, and remember that painting rates will vary depending on where you’re located, the experience level of your tradie, the paint you choose, and a few other things that we’ll delve into in more detail later. If you want more information on interior painting costs, check out our painting cost guide.
Several key factors will impact the final cost of your interior painting project:
Keep in mind: Interior painting does more than refresh your living spaces—it also provides essential protection for your walls against everyday wear, moisture damage, and general deterioration.
If you’re tackling a DIY painting project and need to figure out how much paint to buy, start by measuring the square meterage of all the surfaces you plan to paint—we covered this calculation method earlier in the article.
Most paint tins display their coverage rate on the label. As a general rule, one litre of paint covers approximately 4–12 square metres, though this varies by brand and paint type. Keep in mind that textured or porous surfaces like brick or render will absorb more paint, requiring additional product to achieve proper coverage.
Remember to factor in the number of coats you’ll need—this is especially important when painting over dark colours or concealing wall imperfections. It’s also smart to purchase slightly more paint than your calculations suggest. This gives you a buffer for application errors and ensures you have matching paint on hand for future touch-ups.
Want to skip the manual calculations? Our painting calculator above does the work for you. Simply enter your room’s exact square meterage, and it’ll instantly calculate how many litres you need.
While it might be tempting to grab a brush and tackle your painting project yourself, hiring a licensed professional painter is genuinely the smarter choice.
Professional painters bring expertise in surface preparation, material selection, and application techniques that ensure a flawless finish. When issues arise—uneven coverage, drips, or premature peeling—they have both the knowledge and tools to correct them efficiently, something that can take DIYers multiple attempts to resolve.
The data backs this up: In a recent hipages customer survey, painting topped the list of DIY disasters, with homeowners reporting significant regret about their attempts.
The consequences extend beyond aesthetics. Among those who attempted DIY painting projects:
Beyond the financial and time costs, there’s an emotional toll—living with subpar results in your own home affects your daily comfort and satisfaction.
The solution? Connect with experienced painters who can deliver professional results the first time, saving you time, money, and the frustration of a failed DIY attempt.
When comparing house painting quotes, price shouldn’t be your only consideration. Take time to evaluate each painter’s track record by reading verified reviews on platforms like hipages, and confirm they hold proper licensing and insurance coverage.
Essential Questions to Ask Potential Painters:
Your Role in Getting an Accurate Quote
A successful painting project requires clear communication from both sides. To help your painter provide an accurate quote, be thorough when describing your project:
The more detailed information you provide upfront, the more accurate your quote will be—and the less likely you’ll face unexpected costs once the work begins.
How far will 1 litre of paint go?
Coverage varies by brand and paint type, but as a general guide, one litre of paint covers approximately 14–16 square metres. Dulux confirms this range for their products. Keep in mind that actual coverage depends on the paint formulation and the condition of your surface—rough, porous, or previously unpainted walls will absorb more paint and reduce coverage.
How much do painters charge per m² in Australia?
Most professional painters in Australia charge between $60 and $100 per square metre for interior painting work. The exact rate depends on several factors including your location, the painter’s experience level, the type and quality of paint being used, the complexity of the job, and the amount of preparation work required.
How do you calculate the cost of painting?
To estimate your painting cost, multiply the total square metres of wall and ceiling space by your painter’s per-square-metre rate. Remember to factor in additional expenses such as surface preparation, repairs, primer, specialty finishes, and multiple colours. For a quick estimate tailored to your project, try our house painting cost calculator above—just input your room dimensions and it’ll provide an instant breakdown.
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