How to Choose the Right Sofa Size: The Ultimate UK Measurement Guide 2025

The most common—and expensive—sofa-buying mistake isn't choosing the wrong color or style. It's buying the wrong size. A sofa that's too large overwhelms your room and blocks walkways. Too small, and it looks lost and provides inadequate seating. Both mistakes cost hundreds of pounds and months of regret.

This comprehensive guide eliminates guesswork with exact measurements, practical formulas, and real-world advice from UK homes (where Victorian terraces, new builds, and period flats all demand different approaches). You'll learn precisely what size sofa fits your space, lifestyle, and needs.

Why Sofa Size Matters More Than You Think

Beyond aesthetics, the wrong-sized sofa causes daily frustrations:

Blocking radiators or doorways
Preventing curtains from opening fully
Awkward traffic flow (bumping into coffee tables)
Unusable corner spaces
Can't recline properly
TV viewing distance wrong
Won't fit up stairs/through doorways (delivery disaster)

The right-sized sofa solves all these problems. Let's work out what "right" means for your space.

Step 1: Measure Your Room (The 15-Minute Exercise That Saves £500+ Mistakes)

Essential Room Measurements

Grab a tape measure and note:

1. Room dimensions:

Overall length × width
Ceiling height (for visual proportions)

2. Wall space where sofa will go:

Available wall length
Distance from corner to corner (if using corner space)

3. Obstacles and features:

Radiator positions and sizes
Door swing areas (doors need 90cm clearance minimum)
Window sill heights and positions
Skirting board depth (usually 2-3cm, but period homes can be 8-10cm)
Electrical outlets (you'll want access)
Architectural features (chimneys, alcoves, built-ins)

4. Access routes:

Doorway widths (including frame)
Hallway widths
Staircase width and turning points
Lift dimensions (if applicable)

Pro tip: Photograph your space with tape measures visible. Refer to photos while shopping to avoid forgetting critical measurements.

The Numbers That Matter Most

Write these down—you'll reference them constantly:

Available wall length for sofa: _____ cm
Maximum sofa depth (from wall to room): _____ cm
Narrowest access route: _____ cm

Step 2: Calculate Your Ideal Sofa Dimensions

Width: The Formula

Maximum sofa width = Available wall length - 30cm (minimum)

Why subtract 30cm?

Allows 15cm breathing room on each side
Prevents "squeezed in" look
Leaves space for side tables or floor lamps
Accounts for skirting boards and architectural quirks

Example:

Wall space: 240cm
Ideal maximum sofa: 210cm
Comfortable range: 180-210cm

For corner/sectional sofas: Measure each wall section separately, then subtract 30cm from each.

Depth: The Overlooked Dimension

Standard sofa depths:

Compact: 75-85cm (including back)
Standard: 85-95cm
Deep/lounging: 95-110cm

Calculate your maximum depth:

Measure from wall to opposite wall
Subtract 120cm (coffee table + walkway)
Remaining space = maximum sofa depth

Example:

Room width: 350cm
Minus 120cm (table + clearance)
Maximum sofa depth: 230cm (plenty of room for any sofa)

If this number is under 85cm, you have a depth problem. Consider:

Narrower coffee table
Remove coffee table (use side tables instead)
Compact-depth sofas specifically
Different room layout

Warning: Reclining sofas need 40-60cm extra depth when extended. Measure the reclining depth, not just upright depth.

Height: Visual Proportion Matters

Standard sofa heights:

Low modern: 75-80cm (including cushions)
Standard: 80-90cm
High-back traditional: 90-105cm

Ceiling height guidelines:

For 2.4m (8ft) ceilings: Choose lower-profile sofas (under 85cm) For 2.7-3m ceilings: Standard height (80-95cm) works well For 3m+ ceilings: Taller sofas (95-105cm) prevent lost feeling

Window consideration: If your sofa sits below a window, the sofa back should be at least 15-20cm below the window sill to avoid blocking light.

Step 3: Choose the Right Sofa Style for Your Space

2-Seater Sofas

Typical dimensions: 140-180cm wide, 75-95cm deep

Best for:

Rooms under 3×3 meters
Studio flats
Bedrooms/home offices
Couples/individuals
Pairing with armchairs

Seating capacity: 2 adults comfortably, 3 children at a squeeze

Examples:

IKEA KLIPPAN: 180cm wide (£149)
IKEA GLOSTAD: 165cm wide (£115)
Compact 2-seaters: 140-150cm wide

Shop 2-Seater Sofas at IKEA

3-Seater Sofas

Typical dimensions: 180-220cm wide, 85-95cm deep

Best for:

Rooms 3×4 meters or larger
Families
Primary living room seating
Balanced room proportions

Seating capacity: 3 adults comfortably, 4-5 for movie nights

Examples:

IKEA KIVIK: 228cm wide (£440)
IKEA EKTORP: 218cm wide (£440)
Standard 3-seaters: 200-220cm wide

Sizing note: "3-seater" varies wildly between manufacturers. Always check actual width in cm, not seat count.

Compare 3-seater sofas in our budget guide

4-Seater Sofas

Typical dimensions: 220-280cm wide, 85-100cm deep

Best for:

Large living rooms (4×5 meters minimum)
Families with 4+ people
Entertaining regularly
Open-plan spaces

Seating capacity: 4-5 adults

Warning: Measure access routes carefully. Sofas over 240cm often can't navigate UK staircases and doorways.

Corner Sofas / L-Shaped Sofas

Typical dimensions:

Short side: 150-200cm
Long side: 220-280cm
Total footprint: Often 2.5×2.5 meters minimum

Best for:

Large square or L-shaped rooms
Open-plan living
Maximizing seating
Creating room division

Measure both sections:

Short return section length
Main section length
Total depth when configured

Common mistake: Assuming corner sofas save space. They actually require more room than equivalent linear sofas—but provide more seating.

Browse Corner Sofas at IKEA

Read our corner sofa buying guide

Sofa Beds

Typical dimensions:

Closed: Same as equivalent standard sofa
Open: Add 100-150cm depth for bed extension

Critical measurement: Measure depth from wall to opposite obstacle. Sofa beds need clear space in front to pull out.

Minimum room depth for sofa bed:

2-seater sofa bed: 280-320cm
3-seater sofa bed: 300-350cm

Shop Sofa Beds on Amazon UK

Step 4: Essential Clearances and Spacing

These measurements prevent cramped, awkward layouts:

Coffee Table Clearance

Distance from sofa front to coffee table edge: 40-50cm

Less than 40cm: Knees hit table, uncomfortable to sit
More than 60cm: Can't reach to put down drinks

Traffic Pathways

Main walkways: Minimum 80cm wide Secondary paths: Minimum 60cm

If your sofa blocks the natural walking route, it's too big or wrongly positioned.

TV Viewing Distance

Optimal distance = Screen size × 1.5 to 2.5

Examples:

43-inch TV: 165-275cm (1.65-2.75m)
55-inch TV: 210-350cm (2.1-3.5m)
65-inch TV: 250-415cm (2.5-4.15m)

If your sofa puts you outside this range, either:

Choose different TV size
Reposition sofa
Accept suboptimal viewing (not recommended)

Wall Clearance

Sofas need 5-10cm breathing room behind even when pushed to wall. This prevents:

Damaging wall paint
Blocking skirting boards from view
Trapping cables tightly
Looking "jammed in"

Exception: Built-in banquettes deliberately fit tight to walls.

Radiator Clearance

Minimum 10-15cm between sofa back and radiator

Blocking radiators:

Reduces heating efficiency (wastes money)
Can damage sofa fabric over time
Makes room colder

If radiator is on your sofa wall: Choose narrower-depth sofa or reposition radiator (£150-300 for plumber).

Step 5: Account for Sofa Style Variations

Two sofas both labeled "3-seater, 210cm wide" can feel completely different in your room.

Arm Styles Affect Usable Space

Wide rolled arms: Add 20-30cm per side (total 40-60cm non-seating width) Slim modern arms: Add 10-15cm per side (total 20-30cm) Track/square arms: Add 12-18cm per side No arms: Maximum seating width

Example:

200cm sofa with wide arms: 140cm actual seating
200cm sofa with slim arms: 170cm actual seating

That's 30cm difference—nearly a whole seat cushion.

Back Height and Style

Low backs (under 80cm): Make rooms feel larger, suit modern spaces, less supportive for lounging

High backs (over 90cm): Provide better support, suit traditional rooms, can overwhelm small spaces

Winged/buttoned backs: Add visual weight and depth

Leg vs. No-Leg Designs

Visible legs (15-20cm high):

Make rooms feel larger (visible floor)
Easier to clean underneath
Lighter, more modern aesthetic
Suited to small spaces

Floor-sitting/skirted sofas:

Traditional, formal look
Hides storage underneath (some styles)
Makes rooms feel smaller
Harder to clean under

For small rooms, always choose sofas with visible legs.

Step 6: The Doorway Test (Essential Before Buying)

The #1 delivery disaster: "It won't fit up the stairs."

Measure All Access Routes

Front door opening: Width and height
Hallway: Narrowest point
Staircase: Width, turning points, ceiling height on turns
Room doorway: Width and height
Lift (if applicable): Internal dimensions

The Diagonal Rule

Large sofas often fit through doorways by tilting diagonally.

Formula: Sofa can fit if its diagonal measurement is smaller than doorway diagonal.

Calculate doorway diagonal: √(width² + height²)

Example:

Doorway: 80cm wide × 200cm high
Diagonal: √(80² + 200²) = √46,400 = 215cm
A 210cm sofa can fit if tilted diagonally
A 250cm sofa won't fit without removal of door frame

Critical for corner sofas: Many arrive in sections. Check if your model disassembles.

When Measurements Are Tight

Options if sofa might not fit:

Remove door from hinges (adds 5-8cm clearance)
Remove door frame (professional job, £100-200, adds 10-15cm)
Hoist through window (ground floor only, £150-300)
Choose modular sofa (arrives in sections)
Choose sofa-in-a-box (compresses for delivery)

Professional delivery teams measure access routes before delivery for furniture over £500. Request this service.

Common Sofa Sizing Mistakes (And How to Avoid Them)

Mistake #1: Trusting "Seats X People" Claims

The trap: "3-seater" sounds like it seats 3 adults comfortably.

Reality: Manufacturers measure differently. Some "3-seaters" barely fit 2 adults.

Fix: Ignore seat count. Check actual width in cm. Divide by 60cm per person for realistic capacity.

Mistake #2: Forgetting Sofa Depth

The trap: Focusing only on length, ignoring how far the sofa juts into the room.

Reality: Deep sofas (95cm+) steal significant floor space.

Fix: Measure room depth and calculate backwards: room depth - 120cm = maximum sofa depth.

Mistake #3: Measuring Just the Wall

The trap: "The wall is 250cm, so a 240cm sofa fits perfectly!"

Reality: Sofas crammed wall-to-wall look squeezed and prevent adding side tables or lamps.

Fix: Always subtract at least 30cm from available wall length.

Mistake #4: Showroom Illusion

The trap: Sofas look perfect in massive showrooms.

Reality: 5,000 sq ft showrooms make every sofa look small.

Fix: Measure the showroom sofa and visualize it in your actual room dimensions. Better yet, tape out the dimensions on your floor before visiting showrooms.

Mistake #5: Ignoring Ceiling Height

The trap: All focus on floor dimensions.

Reality: Tall sofas in low-ceiling rooms feel oppressive.

Fix: Match sofa height to ceiling height (see Step 2).

Mistake #6: Recliner Oversight

The trap: Measuring upright position only.

Reality: Recliners need 40-60cm extra depth when extended.

Fix: Ask for "reclined depth" measurement, not just standard depth.

Room Size Guidelines: What Size Sofa for Your Space?

Very Small Rooms (Under 3×3 meters)

Best choice: 2-seater, 140-170cm wide Alternative: Small 2-seater + single armchair Avoid: Anything over 180cm, corner sofas

Example products:

Compact 2-seaters under 160cm
Apartment-sized sofas
Loveseats

Small Rooms (3×3 to 3×4 meters)

Best choice: 2-seater (170-190cm) or compact 3-seater (180-200cm) Alternative: 2-seater + armchair Avoid: Sofas over 220cm, large corner sofas

Example products:

IKEA KLIPPAN (180cm)
Standard 3-seaters under 200cm

Medium Rooms (3×4 to 4×5 meters)

Best choice: 3-seater (200-230cm) Alternative: Small corner sofa, or 3-seater + 2 armchairs Avoid: Sofas over 250cm unless room is closer to 4×5m

Example products:

IKEA KIVIK (228cm)
IKEA EKTORP (218cm)
Most standard 3-seaters

Large Rooms (Over 4×5 meters)

Best choice: Large 3-seater (230-280cm), 4-seater, or corner sofa Alternative: Two 3-seaters facing each other Consider: Modular sectionals

Example products:

4-seater sofas
Large corner/L-shaped sofas
Modular sectionals

Open Plan Living

Best choice: Corner sofas or modular sectionals to define zones Alternative: Floating sofa (pulled away from wall) with console table behind Consider: Scale up one size from your measured space—large open areas need substantial furniture

Quick Reference: Sofa Size Cheat Sheet

| Room Size | Recommended Sofa Width | Sofa Style | |-----------|----------------------|-----------| | Under 3×3m | 140-170cm | Compact 2-seater | | 3×3m to 3×4m | 170-200cm | 2-seater or small 3-seater | | 3×4m to 4×4m | 200-230cm | Standard 3-seater | | 4×4m to 4×5m | 220-260cm | Large 3-seater or small corner | | Over 4×5m | 240cm+ | Large 3-seater, 4-seater, or corner |

Note: These are guidelines, not rules. Your specific room layout, other furniture, and personal needs may vary.

How to Visualize Sofa Size Before Buying

Method 1: Tape It Out

Most effective visualization technique:

Use masking tape on your floor
Mark out sofa dimensions (length × depth)
Live with it for 2-3 days
Walk around it, sit in the area, watch TV
Adjust if it feels wrong

Costs £3 for masking tape, saves £500+ on wrong purchase.

Method 2: Cardboard Mock-Up

Find large cardboard boxes
Cut/arrange to sofa dimensions
Position in room
Assess traffic flow and visual proportion

Bonus: Helps visualize height too.

Method 3: Use Existing Furniture

Rearrange existing furniture (even from other rooms) to approximate sofa footprint.

Method 4: AR Apps

Some retailers (IKEA, Wayfair) offer augmented reality apps that project furniture into your space via smartphone.

Usefulness: Good for general sense, but don't rely solely on apps—always measure properly.

Special Considerations

Period Properties

Victorian/Georgian terraces often have:

Narrow doorways (75-80cm)
Narrow staircases
Tall ceilings (suit taller sofas)
Deep skirting boards (reduce usable wall length)

Best choice: Modular or sofa-in-a-box for delivery, higher-backed sofas for proportions.

New Builds

Modern new builds often have:

Wider doorways (80-90cm)
Lower ceilings (2.4m)
Open-plan layouts

Best choice: Lower-profile sofas (under 85cm high), consider corner sofas for open plan.

Rentals

Best choice: Mid-sized flexible sofas (190-210cm) that work in various layouts, avoid built-in or oversized pieces.

Family Homes

Priority: Durable, washable, adequately-sized seating Best choice: 3-seater (220-240cm) or corner sofa Consider: Removable, washable covers (IKEA KIVIK, EKTORP)

Budget Sofas in the Right Size

You don't need expensive sofas—you need the right size:

Under £200 (Small Spaces)

IKEA GLOSTAD 2-seater (165cm, £115)
IKEA LACK (90cm, £15—more bench than sofa)
Amazon 2-seaters (140-170cm, £150-200)

£200-£400 (Medium Rooms)

IKEA KLIPPAN (180cm, £149)
IKEA KIVIK 2-seater (190cm, £355)
Amazon/Wayfair 3-seaters (180-220cm)

See our full guide to sofas under £500

£400-£500 (Larger Rooms)

IKEA KIVIK 3-seater (228cm, £440)
IKEA EKTORP 3-seater (218cm, £440)
IKEA TORNSBORG sofa bed (450cm, £450)

Browse All IKEA Sofas

Shop Sofas at Wayfair

Final Sofa Sizing Checklist

Before you click "buy," verify:

✓ Sofa width is 30cm less than available wall space ✓ Sofa depth allows 120cm for coffee table + walkway ✓ Sofa height suits your ceiling height ✓ TV viewing distance is screen size × 1.5 to 2.5 ✓ Coffee table clearance is 40-50cm ✓ Traffic pathways are minimum 60-80cm wide ✓ Sofa doesn't block radiators (minimum 15cm clearance) ✓ Sofa fits through narrowest access point ✓ You've taped out or visualized the dimensions ✓ Reclining depth measured if applicable

If you've checked all these boxes, you've chosen the right size sofa.

The Bottom Line

The right-sized sofa:

Fits your room with breathing space (not crammed in)
Provides adequate seating for your household
Allows proper traffic flow (no furniture obstacle course)
Maintains appropriate clearances (40-50cm to coffee table, 15cm+ to radiators)
Fits through your access routes
Suits your ceiling height and room proportions

The formula is simple:

Measure your room properly
Calculate maximum sofa dimensions
Subtract clearances
Choose style that fits those dimensions
Verify access route
Tape out before buying

Most people skip steps 1, 4, 5, and 6—then wonder why their sofa doesn't work. Don't be most people. Spend 30 minutes measuring and calculating now, enjoy your perfectly-sized sofa for the next 7-10 years.

Size matters. Get it right.

Last updated: October 2025. We may earn a commission from purchases made through affiliate links at no cost to you.