How to Finish Backsplash Edges

Finishing the edges of a backsplash is often an overlooked, yet extremely important final step when installing tile. Properly finishing the edges will give your backsplash a clean, finished look that blends seamlessly with the surrounding surfaces. In this comprehensive guide, we will walk through all the key techniques and best practices for finishing backsplash edges like a pro.

Choosing the Right Materials and Supplies

Before starting any edge finishing, make sure you have gathered all the necessary materials and tools:

Tile edging

  • Bullnose tile edges – Specialty finished tiles with one rounded finished edge that covers the rough tile edge. Best for finishing outer edges along countertops or exposed sides.
  • L-shaped tile edges – Angled edging tiles to finish inside corners of backsplashes.
  • U-shaped tile edges – Curved edging tiles for finishing external corners and transitions.
  • Metal tile edge trim – Slim metal strips to finish, protect, or decorate tile edges. Great for transitions.
  • Cove ceramic tile trim – Rounded “cove” shaped ceramic trim for smooth finished edges.

Adhesives and grout

  • Thinset mortar – Modified thinset adhesive suitable for the tile material. Flexible options are best.
  • Grout – Grout that matches the existing backsplash grout color. An epoxy grout is best for water resistance.
  • Caulk – Clear silicone caulk to seal gaps and transitions. Match the caulk color to the grout.


  • Wet saw – For precisely cutting specialty edge tiles and trim pieces to size.
  • Tile nippers – Nippers for snapping tile edges and precision shaping.
  • Grout float – For smoothing and cleaning excess grout from edges.
  • Caulk gun – For applying a consistent silicone caulk bead.

Preparing the Edges

Carefully preparing the edges before installing your finishing tiles or trim is crucial for getting a seamless look:

  • Remove any old caulk, grout, or debris with a utility knife. Scrub the edges clean.
  • Use a file or sandpaper to smooth any rough tile edges. Round over sharp corners.
  • Lightly sand painted edges to roughen the surface so the trim or tiles adhere better.
  • Cut away excess thinset mortar or wall material so edges are flush and even.
  • Fill any gaps wider than 1/8” with silicone caulk and let cure before tiling.
  • Apply modified thinset to the edges per manufacturer instructions. Use an angled applicator tool.

Installing Bullnose Edge Tiles

Bullnose tiles create a rounded finished edge along countertops, open shelves, or any exposed tile side:

  • Measure and cut the bullnose tiles to the required lengths using a wet saw.
  • Dry fit the tiles and make sure the rounded edge completely covers the rough backsplash edges.
  • Apply thinset mortar to the back of the bullnose tiles with the trowel at a 45 degree angle.
  • Firmly press the tiles into place, aligning the rounded edge over the rough edges.
  • Push the bullnose tiles tight to the countertop or wall ends. Use tile spacers for consistent spacing.
  • Clean away excess thinset and let the mortar cure fully.
  • Grout the bullnose tiles, smoothing the grout with a float. Clean excess grout with a sponge and water.
  • After grouting, apply caulk between the bullnose tile and countertop or wall. Smooth the caulk bead with a finger or tool.

Installing L-Shaped Edge Trim

L-shaped tile edge trim creates clean finished inside corners on backsplashes:

  • Measure the length of the inside corners and cut the L-trim pieces to size with a wet saw.
  • Dry fit the trim pieces to ensure they sit flush to both adjoining walls or surfaces.
  • Spread thinset mortar on the back of the L-trim tiles with the trowel at a 45 degree angle.
  • Press the long edge of the L-trim along one wall edge, then adhere the other edge to the adjoining wall.
  • Use tile spacers to maintain even grout lines and make sure the corners are square.
  • Let the mortar cure fully before grouting the L-trim pieces. Smooth the grout into the inside corners.
  • Clean excess grout with water and a sponge. Apply caulk along the top inside edge and smooth with a finger.

Installing U-Shaped Edge Trim

U-shaped edge trim creates finished edges for external corners and countertop to wall transitions:

  • Carefully measure the length needed and cut the U-trim to size using a wet saw.
  • Test fit the trim to ensure it wraps around the corner or transition snugly.
  • Spread thinset mortar on the back of the U-trim, holding the trowel at 45 degrees.
  • Press the trim into place, turning the piece to adhere both sides of the U-shape. Apply firm pressure.
  • Use tile spacers to prevent thinset from oozing into the grout lines.
  • Let the mortar cure fully before grouting. Be sure to pack grout into the curve of the U-trim.
  • Smooth excess grout away with a damp sponge. Apply silicone caulk along the top edges.

Installing Metal Tile Edge Trim

Metal edge trim adds decorative detail and protects edges:

  • Measure and cut metal trim strips to the required length using snips.
  • Dry fit the trim along the edges, mitering the corners at 45 degree angles.
  • Apply thinset mortar to the back of the trim pieces and press firmly in place along the edges.
  • Use painters tape to hold the mitered corners tightly together as the thinset cures.
  • Grout the trim pieces and wipe away excess. Apply caulk along the top edges if needed.
  • For added durability, consider soldering metal trim corners before installation for seamless mitered joints.

Installing Cove Ceramic Tile Trim

Cove trim has a rounded profile that creates smooth, finished edges:

  • Carefully measure and cut the cove trim to the proper size using a wet saw.
  • Test fit the trim to ensure the curved edge fully covers the edge of the tiles.
  • Apply thinset to the back of the cove trim, holding the trowel at a 45 degree angle.
  • Firmly press the cove trim into place along the edges, aligning the curved section over the tiles.
  • Use spacers to prevent thinset from oozing into grout lines. Allow the mortar to fully cure.
  • Grout the cove trim, packing the grout tightly into the curved profile. Smooth away excess grout.
  • Apply caulk along the top outer curved edge if needed to seal any gaps.

Grouting and Caulking Edge Tiles

It’s crucial to properly grout and caulk bullnose, trim, and other edge tiles:

  • Always wait the recommended time for the mortar to fully cure before grouting.
  • Pack grout tightly into corners, curves, and angles to prevent cracks.
  • Smooth excess grout away with a damp grout float or sponge to prevent hazing.
  • After grouting, apply a bead of matching silicone caulk along any gaps. Smooth with a finger or caulking tool.
  • For the best water resistance, use an epoxy grout formulated for kitchens and bathrooms.
  • Polish off any dried grout residue or film with a soft, dry cloth.

Top Tips for Perfect Finished Edges

Follow these pro tips and tricks to help ensure your finished backsplash edges look flawless:

  • Wrapping the tiles or trim just an 1/8” onto adjoining walls helps hide any uneven cuts.
  • Miter inside and outside corners for the cleanest transitions between edges.
  • Plan the tile layout so trim or bullnose edges don’t meet at corners where misalignment is visible.
  • Cut extra length on specialty tiles and trim to allow for adjustments during dry fitting.
  • Use a tile wet saw fitted with a diamond blade for the cleanest, most precise specialty tile cuts.
  • Pre-seal porous natural stone edges before installation to prevent grout and mortar staining.
  • Select grout in a darker color than the tile or trim for a minimally visible finished edge.
  • Apply caulk matching the grout color along bullnose or trim edges for an invisible transition.

With the right materials, careful planning, and proper technique, you can achieve flawless finished edges on your backsplash project. Follow the techniques outlined above, take your time, and pay close attention to detail for polished results. Beautifully finishing the edges makes all the difference in creating a truly pro backsplash installation.

Frequently Asked Questions

How do you finish tile that has no bullnose?

For tile without a bullnose edge, there are several finishing options:

  • Use an L-shaped or U-shaped tile edge trim to cover rough edges on inside and outside corners.
  • Install metal edge trim strips for a sleek finished edge and added protection.
  • Apply cove trim with a rounded profile to smoothly cover sharp edges.
  • Carefully grind rough edges with a stone rasp or sandpaper to create a rounded finished edge.

Should you caulk where backsplash meets countertop?

Applying a silicone caulk bead where the backsplash tiles meet the countertop is highly recommended. The caulk seals any gaps, providing waterproofing and preventing debris, spills and grime from collecting in crevices. Match the caulk color to the grout for a seamless look.

What is the best way to finish an edge near a window?

For edges along windows, use a bullnose tile trimmed to sit just below the window frame or sill. You can also install metal trim or extra tile trim pieces with a polished edge to cover rough window edges. Apply caulk between the tile and window trim for a watertight seal.

Should you use bullnose tile on the bottom edge too?

Using bullnose tile along the bottom edge is an optional finishing choice. A bottom bullnose gives the backsplash a free-floating look. For a built-in appearance, the bottom edge can be left unfinished, but be sure to caulk along the seam between the countertop and tiles.

What is the best way to finish an outside corner?

For finishing an external outside corner, a U-shaped tile trim is ideal. Cut the trim legs to size and install snugly into the corner. A bullnose tile wrapped around the corner also works well. For simple square corners, miter cutting metal trim creates a clean finish.

How do I hide an uneven edge between the backsplash and wall?

If the backsplash edge meets the wall unevenly, use trim or bullnose tile cut slightly wider to overlap the wall by 1/8 inch or so. The small overlap will hide an uneven seam. You can also cut the tiles at a slight angle or ‘bevel’ for a tapered overlap onto the wall.


Finishing tile edges is the hallmark of a professionally installed, quality backsplash. While the process involves careful measuring, precision cutting, and attention to detail, the variety of edge finishing options available means you can customize the finished look. Planning the finished edges from the beginning will ensure your backsplash edges align, complement the overall tile design, and stand the test of time. With these techniques for expertly finishing backsplash edges, you can elevate your tile project with a truly seamless, integrated, and polished look.