How to Edge Subway Tile Backsplash

Edge finishing is one of the most important steps when installing a subway tile backsplash. A clean, finished edge can take your backsplash from drab to fab. While edging may seem intimidating, with the right tools and techniques, you can achieve a professional look. In this comprehensive guide, we’ll walk you through all the steps and tips for edging subway tile backsplash like a pro.

Gather the Right Supplies

Edging a subway tile backsplash requires just a few simple supplies:

  • Tile edging trim
  • Tile adhesive
  • Notched trowel
  • Grout
  • Grout sealer
  • Sponge
  • Tile spacers (if needed)
  • Utility knife
  • Wet saw or angle grinder (for cutting tile)

Choose tile edging trim in materials that match or complement your subway tiles. Metal, stone, bullnose, and PVC trim options are commonly available. Make sure to get tile adhesive suitable for your tile material.

For grout, we recommend an epoxy-based option for the best waterproofing and durability. Match the grout color with your edging trim and tile color. Having all supplies on hand before starting will make the installation process smoother.

Prepare the Surface

Proper surface prep is crucial for a successful installation. Start by ensuring the surface is clean, dry, and free of debris. Use a putty knife to scrape off any old caulk or grout remnants.

Check for any uneven spots and fill as needed with thinset mortar. This will provide a flat, consistent surface for the edging trim and tiles.

If installing near countertops or cabinets, apply painter’s tape along the edges to protect the surrounding surfaces. Your prep work will provide the ideal base for edging and tiling.

Cut the Edge Trim Pieces

Measure and cut edge trim pieces to fit along all exposed edges of the backsplash area. Use a wet saw or angle grinder with a diamond blade to cut the edging trim cleanly and accurately.

Work slowly and carefully during cutting. It’s better to sneak up on the line than to cut the piece too short.

For outside corners, cut the edging at a 45 degree mitered angle. This will allow the pieces to join together smoothly.

Cut several small test pieces first to ensure proper fit before cutting the final trim. Smooth cut edges will give a professional finish.

Apply the Trim

With the surface prepped and trim pieces cut, you’re ready for installation. Apply a generous amount of tile adhesive to the back of the edge trim using a notched trowel.

Press the trim firmly into place along the edges and outside corners. Use tile spacers to maintain even spacing between trim and tile edge. Nippers can help manipulate the trim around corners and bends.

Immediately wipe away any excess adhesive. Allow the trim adhesive to cure fully before moving to the next steps. Proper adhesion will prevent edges from lifting later on.

Install the Subway Tiles

With edging trim in place, start setting the subway tiles. Apply thinset mortar evenly across the surface where tiles will go using a notched trowel.

Press tiles into the mortar, using spacers for consistent gaps. Cut subway tiles as needed to fit around outlets, corners, and edges.

Let the thinset cure fully before grouting, usually about 24 hours. Carefully installing the tiles allows the edging to really stand out.

Grout and Seal the Tiles

Now it’s time to finish it off with grout. Apply epoxy grout using a rubber grout float or squeegee. Push into joints firmly, making sure no gaps or pinholes remain.

Wipe away excess grout with a damp sponge in diagonal motions. Don’t overwash the grout or you may pull it out of the joints.

Once the grout has cured fully, apply a penetrating grout sealer using a small foam brush. This adds an extra layer of protection from moisture and stains.

After sealing, stand back and admire your freshly edged subway tile backsplash! The finished look will be clean, streamlined, and modern.

Helpful Tips and Tricks

  • Stagger subway tiles in a bricklaid pattern for the most visually appealing look
  • Use plastic tile spacers to maintain even grout line width
  • Plan an extra 10-20% in tile and supplies for cuts, mistakes, etc
  • Work in small sections for easier installation and less thinset drying
  • Tile leveling systems can help keep tiles perfectly flush
  • Use masking tape when applying sealer to avoid getting it on the tile surface
  • Check for lippage and use a rubber mallet to tap down any raised edges

Common Questions

How do I get clean edges along the countertop?

Use a utility knife to slice any thinset or mortar that gets on the countertop edge before it dries. Painter’s tape along the countertop before tiling can also prevent messes.

What color grout should I choose?

Match the grout color with your edging trim for the most seamless look. White and light grey are common colors that work with most subway tiles.

Can I use bullnose trim on the edges?

Yes, bullnose trim is a great option to finish subway tile edges for a rounded look. The installation process is the same as standard edging.

How do I cut the subway tiles cleanly?

Use a wet saw with a sharp diamond blade designed for cutting tile. Take your time and hold tiles steady for precise cuts.

Edge finishing is the secret weapon that takes subway tile backsplash from basic to beautiful. With some careful planning and attention to detail, you can achieve perfectly framed backsplash edges. Just take your time, use the right materials and tools, and your edges will come out looking sharp.


Installing subway tile edging trim is a great upgrade to make over leaving raw tile edges exposed. Prepping the surface, cutting precise trim pieces, applying with thinset adhesive, grouting, and sealing results in a clean finish that really elevates the look. Focus on working slowly and carefully for the best outcome. Finishing your backsplash properly will help it last for many years of style and functionality. With the right know-how, you can edge subway tiles like an expert.