How to Paint a Window Sill: What You Need to Know

The average window sill goes through its fair share of wear and tear. Not only do we use them as a place to stand everything from vases and pictures to candles and ornaments, but they also have to stand up to damage from sun, rain and condensation. With all that in mind, it’s no surprise that we like to treat them to a fresh lick of paint every few years.

Repainting your window sills is a simple task that can really brighten up your home. For that reason, estate agents often recommend giving them a new paint job to wow prospective buyers. Of course, there’s no reason why you shouldn’t take the time to repaint them even if you’re not looking to sell. After all, everyone wants their home to look its best!

Want to find out more about how to paint window sills? You’ve come to the right place! Read on for our simple step-by-step guide.


What tools and materials do you need to paint a window sill?

First of all, you’ll want to make sure that you have the necessary tools for the task.

Reassuringly for anyone who’s not naturally gifted at DIY, in most instances you won’t need anything too complicated. We recommend the following tools and materials, listed in alphabetical order:

  • Angle paintbrush
  • Drop cloth
  • Medium-grit sandpaper
  • Painter’s tape
  • Primer
  • Putty knife (or a five-in-one painter’s tool)
  • Sanding block
  • Semi-gloss paint
  • Spackle
  • Sponge or rag
  • White vinegar

What tools do you need to paint a window sill

A warning on lead paint

If you live in an older home, there’s a chance your window sills might have been decorated with lead paint. Naturally, you don’t want to risk exposing your family to this harmful substance, so consider hiring a specialist to carry out an inspection.


How to prepare your window sill before painting

There are a few steps to perform before you start repainting your window sills:

  1. Lay your drop cloth down under the area you’ll be painting to protect your floor or carpet from being covered in paint drips.
  2. Likewise, move any furniture away from the window. If necessary, cover it over with a sheet or tarpaulin.
  3. Do you have air vents near your window? Cover or close them to prevent dust and paint chips from being spread throughout your home.
  4. Use your putty knife or five-in-one painter’s tool to remove as much of the old paint as possible – but only the loose paint. Don’t try to force it off.
  5. Fill in any holes in the window sill with spackle, applying a small amount each time. Allow it to dry before you start painting.
  6. If you’re left with rough or uneven sections of window sill, smooth them down using the medium-grit sandpaper.
  7. Clean the surfaces using a combination of white vinegar and warm water until the window sills are free of grit and dust.
  8. Affix painter’s tape around the area you’re planning to paint.

Painting a window sill white

How to paint window sills without streaks

Now that you’ve completed those essential preparations, it’s time to paint your window sill! Use the following steps for a quality, streak-free finish:

  1. Prime the scraped and cleaned window sill using primer and an angled brush. The angle of the brush makes it easier to reach any ridges or nooks in the woodwork.
  2. Leave the primer to dry completely. This can take anywhere from one to three hours, but varies depending on the primer you’re using. Check the tin for details.
  3. Paint your window sill using long, smooth strokes. Choose a paint that is easy to clean and hard-wearing. Gloss or semi-gloss acrylic or latex enamel paints are perfect, as they level out into a smooth, professional-looking surface.
  4. Once the paint has dried, apply a second coat if necessary.
  5. Remove the painter’s tape and enjoy your good-as-new window sill!


Of course, some window sills are sadly beyond saving with a lick of paint! If you need brand new window sills, we’ve got you covered with our wide variety of MDF sills and boards. Browse the full range here.