A shop fascia sign does far more than display your business name. It helps create a first impression, reinforces your branding and plays an important role in attracting passing customers.
One of the biggest decisions when designing a new shop front is choosing the right material. Different materials offer different levels of durability, depth and visual impact, so understanding the options can help you make the right investment.
What Thickness Should Acrylic Letters Be?
Acrylic letters are one of the most popular choices for business signage because they offer a clean, professional and versatile finish. They can be used for shop fronts, reception signs, office walls, window displays and branded interior features.
One of the most common questions customers ask is: what thickness should acrylic letters be?
The answer depends on where the letters will be installed, how large they are, how far away they need to be read from and what type of finish the business wants to achieve. A small reception sign does not need the same letter thickness as a shop fascia on a busy high street.
Why Acrylic Letter Thickness Matters
The thickness of acrylic letters affects both appearance and performance. Thinner acrylic can look subtle and refined, while thicker acrylic creates more depth and a stronger three-dimensional effect.
Thickness also affects durability. If the letters are too thin for the size of the sign, they may look weak or feel less substantial once installed. If the letters are too thick for a small interior wall sign, they may appear bulky and out of proportion.
From a production perspective, the thickness must also work with the artwork. Very thin strokes, delicate. serifs and small details can become difficult to cut cleanly, especially when the letters are being produced at a small size.
This type of signage is closely related to our Flat Cut Letters service.
3mm Acrylic Letters
3mm acrylic is usually suitable for small internal signs, lightweight wall lettering and subtle branding applications. It can work well for office interiors, plaques, directional signs and small logo details where the viewing distance is short.
However, 3mm acrylic can feel quite flat when used for larger signs. It does not create much depth, so it is best used when the design needs to look discreet rather than bold.
For production, 3mm acrylic also needs careful artwork checking. Thin strokes and fragile details can become risky, especially on smaller letters. As a general rule, a minimum stroke width of around 5mm is preferred for acrylic letters. A 3mm stroke may sometimes be possible, but it depends heavily on the font, size and fixing method.
5mm Acrylic Letters
5mm acrylic is one of the most commonly used thicknesses for flat cut letters. It offers a good balance between clean appearance, practical production and cost efficiency.
For many shop signs, reception walls and office branding projects, 5mm acrylic provides enough depth to create a professional finish without looking too heavy. It is also suitable for a wide range of colours and finishes, including gloss, matt and wet-coated finishes.
On a shop fascia, 5mm acrylic letters can work well when mounted to an aluminium composite panel, sign tray or painted wall. For internal signage, it gives a more premium appearance than thin flat graphics while still keeping the design refined.
This thickness is often a sensible starting point for businesses looking for a clean, modern result.
10mm Acrylic Letters
10mm acrylic letters create a noticeably stronger three-dimensional effect. They are suitable when the sign needs more presence, especially in reception areas, feature walls and premium retail environments.
Compared with 5mm letters, 10mm acrylic feels more substantial and architectural. It is often chosen when the sign is part of an interior design scheme rather than simply a functional name display.
For larger lettering, 10mm acrylic can help the sign look more proportional. It also casts stronger natural shadows, which can make the branding stand out more clearly against the wall or fascia.
This thickness works particularly well with simple, bold letterforms. Delicate fonts can still be used, but the artwork must be checked carefully to make sure all strokes and joins are strong enough for cutting and installation.
20mm Acrylic Letters
20mm acrylic letters are used when a more premium and dimensional appearance is required. They create strong depth and are often selected for high-end retail, hospitality, office reception areas and branded feature walls.
At this thickness, the letters begin to feel more like architectural signage rather than flat decorative lettering. The side profile becomes part of the design, so colour, finish and edge quality are especially important.
20mm acrylic can also be wet-coated to achieve specialist colours and finishes. This is useful when a brand requires a specific metallic, matt or satin effect.
For larger shop front signs, 20mm acrylic letters can deliver excellent visual impact while remaining cleaner and more cost-effective than fully fabricated built-up letters.
When to Choose Built-Up Letters Instead
Acrylic letters are a strong option for many projects, but they are not always the best solution. If the sign needs greater depth, illumination or a more premium external appearance, built-up letters may be more suitable.
Built-up letters are constructed with returns, giving them a deeper profile than flat cut acrylic. They can also be combined with LED illumination for halo-lit or face-lit effects, making them ideal for shop fronts, restaurants and evening visibility.
For businesses comparing flat acrylic letters with deeper dimensional signage, the choice often comes down to budget, viewing distance and the level of impact required.
This type of signage is closely related to our 3D & Built-Up Letters service.
Internal vs External Acrylic Letters
Internal acrylic letters are usually easier to specify because they are protected from weather exposure Reception signs, office wall logos and interior branding can often use 5mm, 10mm or 20mm acrylic depending on the desired appearance.
External acrylic letters need more careful consideration. Shop fronts are exposed to weather, temperature changes, cleaning and everyday wear. The fixing method, substrate and letter size all affect which thickness is appropriate.
For external signs, 5mm acrylic can work well for many standard fascia applications, especially when the letters are not too large. Larger signs may benefit from 10mm or 20mm acrylic to improve presence and strength.
Acrylic lettering for shop fronts often forms part of a wider sign system, alongside aluminium composite panels, sign trays, window graphics, projecting signs or lighting.
This type of work is closely related to our Shop & Retail Signs service.
How Letter Size Affects Thickness
Acrylic thickness should always be considered together with letter height. A small 100mm high letter does not need the same thickness as a 600mm high fascia letter.
For small internal letters, 3mm or 5mm acrylic may be enough. For medium-sized reception letters, 5mm or 10mm is often more suitable. For large feature wall letters or shop fascia letters, 10mm or 20mm can create better proportion and visibility.
The font also matters. A bold sans-serif logo will usually be easier to manufacture than a thin script font. Thin lines, sharp joins and delicate shapes may need to be enlarged or adjusted to avoid weak areas.
Fixing Methods Also Matter
The thickness of the acrylic is only part of the decision. The way the letters are installed also affects the finished result.
Letters can be fixed directly to the wall or fascia for a clean, flat appearance. They can also be mounted on stand-off locators to create a small shadow gap, which gives the sign more depth. For exterior signage, the fixing method must be secure enough to handle weather conditions and long-term use.
Heavier or thicker letters need suitable fixings and accurate installation. This is why a site survey is important, particularly when signs are being installed onto existing shop fronts, tiled walls, cladding or uneven surfaces.
A Practical Thickness Guide
For subtle internal signage, 3mm acrylic can be suitable, provided the artwork is not too delicate.
For most standard flat cut letters, 5mm acrylic is usually a strong and practical choice. It works well for office signs, shop fascias and reception branding.
For a more premium interior sign or larger lettering, 10mm acrylic adds depth and improves visual impact.
For high-end reception signs, luxury retail branding or bold shop front lettering, 20mm acrylic creates a more substantial and architectural finish.
The best option depends on the size of the letters, the viewing distance, the location and the overall style of the business.
Fabrication and Installation Considerations
Before acrylic letters are manufactured, the artwork should be checked carefully. Thin strokes, sharp corners and small counters can all create production issues if the letters are too small.
A minimum stroke width of around 5mm is generally preferred for acrylic letters. Smaller details may be possible, but they can become fragile depending on the design and material thickness.
For larger signage, panel sizes, access requirements and installation conditions also need to be considered. Good signage is not only about choosing a material. It is about making sure the design can be produced, fixed securely and read clearly from the intended viewing distance.
Looking for Acrylic Letters for Your Business?
Whether you need subtle reception lettering, premium office branding or acrylic letters for a shop front, choosing the right thickness helps ensure your signage looks professional and performs properly over time.
If you have further questions, feel free to call us on 020 7350 1567 or emailing info@yellowsigns.co.uk, our team will help you get it right before production.