How to Finish Off Backsplash Tile


Installing a backsplash is a great way to add visual interest and protect the walls behind sinks, stoves, and countertops from water damage and stains. While the tile itself often gets the most attention, properly finishing off the edges of the backsplash is equally important for a seamless look. There are several techniques for finishing off backsplash tile depending on the type of edge and transition needed.

In this comprehensive guide, we will walk through the steps and best practices for finishing off backsplash tile for a polished, professional result. We will cover how to treat inside and outside corners, edges along countertops and cabinets, connections to other surfaces, and the top edges of the backsplash itself. With the right materials and techniques, you can achieve clean lines and elegant transitions for a backsplash that looks like it was done by the pros.

Preparing the Surface

Before installing any backsplash tile, it is important to start with a clean, smooth, and flat surface. Any pits, bumps, or irregularities in the wall can show through and detract from the finished look. Fill any holes or gaps with spackle or joint compound, allow to dry completely, and sand smooth.

It is also advisable to apply a coat of thinset mortar to the entire surface before tiling. This helps create a strong bond and prevents moisture issues behind the tile. Use a notched trowel to spread the thinset evenly across the surface, making sure to fully cover the drywall or other backing material.

Once the thinset has dried, you are ready to begin setting the tile. Be sure to work in small sections so the adhesive does not dry out before tiles are placed. Carefully follow the tile manufacturer’s instructions for setting materials and techniques. Allow the tile to fully cure before grouting or finishing the edges.

Treating Inside Corners

Inside corners, such as where a backsplash meets an adjoining wall or cabinet, require special treatment for a seamless transition. There are a couple options for cleanly finishing inside corners:

Bullnose Tiles

Bullnose tiles have one rounded finished edge that can be used along an inside corner. Set the bullnose tiles as you would standard tiles, aligning the rounded edge along the corner. The curve helps prevent any cracks or uneven lines where the tiles meet. Make sure to use bullnose tiles on both walls forming the corner for the best effect.

Bullnose tiles are available in many of the same materials and finishes as standard wall tiles. Pay attention to the sizing, as you want the bullnose edge to align perfectly with the field tiles. Carefully grout the bullnose tiles just like the others. The finished look will be a smooth, monolithic inside corner.

Corner Joint Trim

Another option for inside corners is to install a metal or plastic corner joint trim piece. These come in a wide variety of colors and finishes to match your tiles. The trim installs over the tile edges, hiding any uneven cuts and giving a straight, clean finish.

Most corner trim pieces have one or two legs that fit over the tile edges. They can be adhered with tile mastic or thinset mortar. Install any field tiles first, leaving a small 1/16” gap at the corner. Then apply tile adhesive and press the trim over both tile edges, aligning it evenly along the length of the corner.

Corner trim is great for situations where two different tile finishes meet at an inside corner. The trim piece bridges the transition and provides extra protection against cracking. Be sure to use a trim tile that coordinates with or matches the colors of your backsplash.

Treating Outside Corners

Outside corners, such as along a wall ending or kitchen peninsula, also require special attention when installing backsplash tile. Here are two effective ways to give outside corners a finished look:

Bullnose Tile Strips

Much like with inside corners, bullnose tiles can be used along outside corners to ease the transition. Cut individual bullnose tiles into strips approximately 2” wide. Apply tile adhesive along the edge of the last field tile and adhere the bullnose strip, aligning one edge with the outside corner.

Continue setting bullnose strips moving outward from the corner. Be sure to cut strips to size if needed to maintain even spacing and grout lines. The bullnose edge helps prevent cracking at the vulnerable outside corner. Make sure to wrap bullnose strips around both sides of the corner for a seamless look.

Decorative End Caps

For a more decorative treatment, install matching tile end caps along the outside corner edge. These interlocking accessories fit over the exposed tile edges, hiding uneven cuts and giving a finished look. End caps come in metal, plastic, or matching tile material.

After setting the last field tile, mark and cut the end cap pieces to fit. Apply adhesive and press into place, interlocking the cap halves along the corner edge. Maintain even spacing and alignment along the entire outside corner. Once installed, the caps should provide a straight edge and protective transition.

Countertop and Cabinet Edges

The edges where backsplash tile meets countertops and cabinets also need special consideration. Even small gaps or uneven lines will be noticeable in these high-visibility areas. Here are some tips:

Match Backsplash and Countertops

The easiest transition is if the countertop and backsplash use similar thicknesses of the same tile material. For example, granite tile countertops work well with matching granit tile backsplash. This allows the tiles to be level and align perfectly.

If the countertop is a different material but similar thickness, you can still get a straight edge by cutting the backsplash tiles along the cabinet line. A coordinated grout color will help blend any minor differences in thickness.

Use Edge Trim

For most other countertop materials, install matching tile edge trim along the top edges of the backsplash. Metal or plastic trim pieces give a straight, finished transition between the countertop and tile. Apply trim after setting the field tiles, leaving a slight gap for the edge trim to fit in.

Make sure to get trim pieces designed for the thickness of your tile. They should adequately cover the tile thickness while also overlapping the front edge of the countertop slightly. Carefully miter trim pieces at corners for the most seamless look.

Caulk Along Edges

Finally, flexible caulk can help bridge any remaining small gaps between tile and countertops or cabinets. After grouting, run a smooth bead of silicone caulk along these edges. Tool the caulk with a finger or caulk spatula for a smooth finish.

Match the caulk color as closely as possible to your grout for the most invisible transition. Caulk provides extra protection against moisture and debris penetrating behind the backsplash.

Top Edges

The uppermost edges of a backsplash also require special treatment, even if they don’t meet a countertop. Exposed tile edges can crack and become damaged over time. Here are some finishing options:

Bullnose Tile

Bullnose tile makes a reappearance here—it can be used to cap off the upper edges of a backsplash for protection and a decorated finish. Measure and cut individual bullnose tiles to fit along the top.

Bullnose tiles should overhang the front, upper edge slightly. Align the rounded front edge with the outside corner for a smooth transition. The bullnose caps will protect the vulnerable corners and soften the transition from tile to wall.

Decorative Trim

For a more decorative look, install matching tile trim pieces along the top edge. Hundreds of metal, plastic, and tile trim styles give you options for a finished look. Simple, straight designs work well for a clean finish.

Measure and cut trim pieces to fit along the top edge, mitering as needed at corners. Leave a slight gap between the field tile and trim to insert the trim ends. Adhere trim with tile mastic or grout for a polished, built-in look.

Painted Edge

If leaving an exposed tile edge, one simple option is to paint it to match the wall. After grouting, use painter’s tape and plastic sheeting to mask off the rest of the tile. Then apply at least two coats of matching wall paint along the raw edge.

Remove tape and sheeting while the paint is still wet to avoid pulling up strips. The painted edge minimizes the visible transition from tile to wall for a seemingly integrated backsplash. Touch up the paint yearly to keep the edge looking neat.

Transitions to Other Surfaces

Backsplashes often meet other surface finishes besides countertops and walls. For example, the area behind a stove may transition from tile to hardwood flooring. Other unique edges require finishing as well:

Transition Strips

Install metal, plastic, or stone transition strips wherever tile abuts another type of flooring. Transition strip thresholds provide a straight, clean edge between two flooring heights or materials. After laying the tile, adhere the strips according to the manufacturer’s directions.

For best results, the tile, thinset, and grout should be level with the top of the transition strip. This prevents uneven ledges between the tile and flooring. The strip then hides the edge and provides extra protection.

Seal Edges

Any tile edges exposed to outside weather require extra protection. Ensure exterior tile has cutoff tops against walls, overhangs, etc. After grouting, apply a flexible silicone sealant along any exposed exterior edges.

Tool the sealant smoothly for a sleek look. This prevents moisture from penetrating behind the tile and causing damage in freeze-thaw cycles or rainstorms. Reapply sealant yearly as needed.

Match Flooring Profile

For finished edges where backsplash tile meets continuous flooring, match the tile thickness and profile to the flooring. For example, 3/8” porcelain tile can align evenly with engineered hardwood flooring. Matching materials and dimensions on the backsplash and floors allows for straight, seamless transitions.

Grouting and Caulking

Grout fills the joints between tiles, locking everything into place and preventing moisture issues. Use sanded grout for joints wider than 1/8” and unsanded for narrower spaces. Always apply grout per manufacturer’s instructions.

Along any gaps or edges, flexible caulk adheres where grout cannot. Silicone caulk expands and contracts to allow for movement. After grouting, run a smooth bead of caulk along all seams and transitions. Tool for a smooth finish and wipe away excess.

Allow grout and caulk to fully cure, usually 24-48 hours. Avoid wetting or scrubbing the applications during this time. Once hardened, they will provide a water-resistant finish.

Maintaining Finished Edges

Your finished backsplash edges will provide many years of beauty and protection. However, some periodic maintenance helps keep everything looking fresh:

  • Inspect edges and re-caulk as needed, at least yearly. Look for any cracks, gaps, or sealant failures and recaulk promptly.
  • Clean grout with aSpecialized grout brush and Grout cleaner to remove stains or haze. Avoid abrasive scrubbing.
  • Re-seal tile or grout as necessary using penetrating sealers made for each material. This prevents staining and moisture damage.
  • Repaint any painted edges yearly to keep the transition crisp and unnoticeable. Use painter’s tape to protect tile.
  • Avoid hanging items directly on backsplash tile to prevent cracking or loosening at vulnerable edges and corners.

With proper installation techniques and occasional maintenance, you can enjoy your beautifully finished backsplash for many years of durability and high style. Well-executed edges make all the difference in taking your backsplash from DIY to designer-quality.

Frequently Asked Questions About Finishing Backsplash Tile

Finishing off a backsplash install requires attention to detail, especially along the exposed edges. Here are answers to some common questions about properly completing a backsplash tile project:

How is bullnose tile different from regular wall tile?

Bullnose tile has one rounded, finished edge that can be installed along corners or countertops. The curved profile helps prevent cracking and chipping for a durable, seamless look. Bullnose tiles are made to match standard wall tiles in dimensions and thickness.

Should I use real tile trim or plastic trim?

Real tile trim provides the most authentic finished look since it actually matches the tiles. However, plastic trim costs less while still offering durability and many color options. Use whichever fits your budget and desired style.

What kind of caulk should I use with tile?

Always use flexible, waterproof silicone caulk rated for tile and stone applications. Avoid standard latex caulks. Make sure to tool the caulk for a smooth finish. Matching the caulk color to your grout provides the most invisible transition.

How do I cut bullnose tiles?

Use a wet saw or tile cutter to cut individual bullnose strips to size. Cut with the rounded edge facing down to avoid chipping. Minor chips can be smoothed with sandpaper. Make precision cuts for tight-fitting installation along edges.

How do I get clean grout lines along trim pieces?

Tape off edges of trim before grouting to prevent haze or staining. Remove tape immediately after grouting. Use a grout bag to neatly apply grout between trim and tiles without smearing. Clean any haze on trim with a soft cloth.

Should tile extend past the upper cabinets to the ceiling?

It is not essential, but installing tile to the ceiling gives a seamless, built-in look. Use trim or bullnose to finish the upper edge. Prepare the wall surface above cabinets to ensure the tile adheres properly.

What should I seal tile edges with?

Use a flexible silicone sealant without silicone oil, made specifically for tile and stone. Avoid standard caulks. Tool the sealant for a smooth finish and wipe away excess. Reapply yearly or as needed to maintain the protective seal.

How do I finish an edge against a window?

If the tile ends flush with the window frame, apply trim or bullnose along the edge, stopping neatly at each corner. If the window interrupts the tile, treat it like a niche and finish around all sides for a clean, framed look.

What’s the easiest way to get perfectly straight grout lines?

Use tile spacers between each tile while setting them. Carefully align the spacers with the edge of adjacent tiles for straight lines. Remove spacers just before grouting each section. Use a grout float at a consistent angle to maintain straight joints.


Finishing off a backsplash tile installation properly not only makes the job look professionally done, but also helps protect the edges and prevent damage over time. Pay special attention to corners, seams, transitions, and exposed edges when planning the materials and techniques.

With the right combination of bullnose tile, trim pieces, caulk, and sealant, you can achieve beautiful, durable finished edges that complement the style of your backsplash. Taking the time to craft clean lines and elegant details will elevate your whole kitchen’s design.