Tog Rating by Season: Which Duvet for Each Time of Year
For a typical UK home, the usual guide is 2.5 to 4.5 tog in summer, 7 to 10.5 tog in spring and autumn, and 12 to 15 tog in winter. These figures match the seasonal ranges listed for temperate climates). The right number for you also depends on your bedroom temperature, your filling and how warm you sleep. This guide gives the chart first, then the adjustments.
Key takeaways
- Summer: 2.5 to 4.5 tog. Spring and autumn: 7 to 10.5 tog. Winter: 12 to 15 tog.
- 13.5 tog is the most commonly recommended winter baseline for UK homes.
- Bedroom temperature is a more accurate guide than the calendar month.
- A duvet cover adds some insulation, so a cover can change how a duvet feels.
- Two lighter layers that combine into one warmer duvet give the most flexibility across the year.
Table of Contents
- Duvet tog chart by season
- What a tog rating measures
- Summer: 2.5 to 4.5 tog
- Spring and autumn: 7 to 10.5 tog
- Winter: 12 to 15 tog
- Room temperature matters more than the month
- Filling, cover and weight: what else changes the feel
- The all-season option: layering
- Our perspective
- Choosing your duvet and cover at Roomie Design
- A quick seasonal checklist
- FAQ
- Sources
Duvet tog chart by season
Use this table as a starting point. The ranges follow the published seasonal guidance) for standard UK and temperate climates.
| Season | Months (UK) | Tog range | Common choices |
|---|---|---|---|
| Summer | June to August | 2.5 to 4.5 | 3, 4.5 |
| Spring | March to May | 7 to 10.5 | 7.5, 9, 10.5 |
| Autumn | September to November | 7 to 10.5 | 9, 10.5 |
| Winter | December to February | 12 to 15 | 12, 13.5, 15 |
The months are a convenience. British weather moves between seasons, so the sections below also give the bedroom conditions behind each range.
What a tog rating measures
Tog stands for thermal overall grade. It measures thermal resistance: how well a material slows heat leaving your body. One tog equals 0.1 m²·K/W, and the figure is ten times the temperature difference between the two faces of the material) under standard test conditions.
In practice:
- A lower tog lets heat pass more easily. It feels light and cool.
- A higher tog holds heat in. It feels warmer and more enclosed.
- The same tog in different fillings can feel different, because the fibres trap air in different ways.
Two details are worth knowing. The same source notes that labelled duvet ratings are often minimums, with real performance up to 3 togs higher). It also notes that the rating assumes a duvet used alone, and that a duvet cover traps extra air and adds insulation. A duvet in a thick cover can feel a little warmer than the label suggests.
Summer: 2.5 to 4.5 tog
Summer duvets are the lightest. A 4.5 tog is the usual choice for warm months in the UK. A 3 tog or 2.5 tog suits very warm rooms, top-floor bedrooms and sleepers who run hot.
What to look for:
- Low tog: 2.5, 3 or 4.5.
- Breathable cover: linen, percale cotton and lyocell move air well. Our guide to summer bedding materials for hot sleepers compares them.
- Breathable filling: natural fibres such as cotton or wool tend to regulate temperature better than synthetics. Good Housekeeping’s UK summer duvet tests give a view of what testers rate in a heatwave.
If you wonder whether a 7.5 or 9 tog is too hot for summer: in a warm bedroom, often yes. In a cooler room, such as a north-facing one or a house with thick walls, a 7.5 tog can still work in June or early September.
Spring and autumn: 7 to 10.5 tog
The shoulder seasons are the hardest to match. Mornings are cold, afternoons are mild and the heating may or may not be on. The range is wide for that reason.
- 7.5 tog: early spring, early autumn or mild bedrooms.
- 9 tog: the middle of the range. A common all-round choice for a bedroom without heating on.
- 10.5 tog: late autumn, or early spring in a cooler room. It also works in winter when the home is consistently well heated.
The published pairings by room temperature put 10.5 tog with bedrooms of 18°C or above). That is why a 10.5 can sit in both the autumn and the winter column.
Winter: 12 to 15 tog
Winter is the season with the highest search interest, and the answer is clearer. 13.5 tog is widely treated as the winter standard for most UK homes. Home experts describe 15 tog as the choice for very cold or poorly insulated properties, or for sleepers who feel the cold. They describe 10.5 tog as suitable if the home stays well heated.
The same temperature pairings put 13.5 tog with bedrooms of 15 to 17°C and 15 tog with bedrooms of 14°C or below).
| Bedroom temperature | Matching tog |
|---|---|
| 18°C or above | 10.5 |
| 15 to 17°C | 13.5 |
| 14°C or below | 15 |
Is 10.5 or 13.5 better for winter? Choose 13.5 if your bedroom drops below about 18°C overnight. Choose 10.5 if you heat the room through the night or share the bed with a warm sleeper.
For cold sleepers, our guide to winter bedding fabrics covers the cover and sheet side. A warm duvet works best with sheets and covers that feel comfortable against the skin on a cold night.
Room temperature matters more than the month
The calendar is a rough guide. Outdoor weather is only part of the picture, because the air around your bed is what the duvet has to work with. Bedroom temperature, heating, insulation and ventilation set the real conditions.
A few practical points:
- Check the room. A cheap thermometer on the bedside table tells you the overnight temperature. Use the table above to choose the tog.
- Think about the building. Top-floor flats hold heat. Older terraces and rooms with single glazing lose it. A damp or condensation-prone bedroom can also feel colder than the thermometer says, so it is worth dealing with before you buy a heavier duvet.
- Remember personal differences. A one-week field study of 33 university students looked at how bedroom thermal conditions relate to comfort and sleep. Comfort varies between people, so use the chart as a start and adjust.
- Wear what suits the night. Sleepwear changes how much duvet you need, and a guide to choosing winter pyjama fabrics shows how much flexibility clothing adds.
Filling, cover and weight: what else changes the feel
Tog is one number. Three other things shape how a duvet sleeps.
Filling. Down and feather are light for their warmth. Wool regulates temperature through the year. Microfibre is a softer, lighter-feeling option at a lower weight. Natural, breathable fillings generally manage heat better than synthetic ones, which is why a lower-tog synthetic duvet can feel less comfortable than a similar natural one.
Cover. Cotton percale feels crisp and cool. Linen is airy and softens with every wash. Mulberry silk is smooth and temperature-regulating against the skin. Sateen cotton feels smooth and a little warmer. Each one changes the feel of the duvet without changing its tog.
Construction. Box stitching holds the filling in place. Even filling means no cold spots across the bed.
Our guide to the role of duvet inserts explains how the insert and the cover work together.
The all-season option: layering
A single duvet for all four seasons is rarely perfect. The practical alternative is a modular set. A common system pairs a 4.5 tog layer with a 9 tog layer. Use the 4.5 alone in summer, the 9 in spring and autumn, and clip them together for a combined winter duvet that reaches roughly 13.5 tog.
The advantages:
- One system covers the full year.
- You adjust for a warm or cool night in minutes.
- Two partners can use different layers on one bed where the set allows it.
- Storage is simpler than three separate duvets.
Layering also works with what you already own. A throw over a lower-tog duvet adds warmth on the coldest nights and comes off when the room warms up. Our guide to adjustable three-layer winter bedding sets out how to build that.
For a full tog explainer with sizing and linen pairings, see our duvet tog rating guide.
Our perspective
We sell bedding, so we see the same pattern in the questions customers ask. People start with the season and finish with the room. A duvet is a system: insert, cover, sheets and pillows each change how a night feels.
Our view, in four points:
- Choose the tog for the bedroom you have, not the month on the calendar.
- Choose the cover for the feel you want. Cotton, linen, lyocell and mulberry silk each give a different texture, and all of them work with a range of togs.
- Treat layering as a normal way to sleep, not a compromise. Adding or removing a layer takes seconds.
- Match sheets and pillowcases to the duvet. A complete set feels more consistent from the first night.
— Roomie Design
Choosing your duvet and cover at Roomie Design
Once you know your tog, the next step is the duvet and the cover. Our Duvets & Bedspreads collection lists the inserts, including the Luxury Metallic All-Season Goose Down Duvet, the Minimalist Down & Feather Duvet and the Down Feel Microfiber/Cotton Duvet. Check each product page for its specifications before you order.
Then pick the cover:
- Duvet Cover Sets in cotton, linen and lyocell, in plain, floral, reversible and farmhouse styles.
- Mulberry Silk Bedlinen for a smooth, premium feel.
- Sheets and Pillowcases to complete the bed.
Size guides, customer reviews, order tracking and multi-currency checkout are available on the site.
A quick seasonal checklist
- Measure the bedroom temperature on a typical night.
- Find the range in the table: 18°C or above, 15 to 17°C, or 14°C or below.
- Pick the tog, then pick the filling.
- Choose a cover for the texture you prefer.
- Add a second layer or a throw if you want to change the warmth through the year.
FAQ
What is a good tog for all seasons?
There is no single perfect figure. A 9 tog is the usual middle choice for a year-round single duvet in a UK bedroom. A two-layer set, such as a 4.5 tog and a 9 tog that clip together, is more flexible because you can use one layer, the other or both.
Is 9 tog too hot for summer?
In most UK summers, a 9 tog is warm. A 4.5 tog is the usual summer rating, and 2.5 or 3 tog suits very warm rooms. A 9 tog can still work in a cool bedroom in early June or September.
Is 7.5 tog too hot for summer?
It depends on the room. In a bedroom that stays warm overnight, 7.5 tog is likely to feel heavy, and 4.5 tog is the safer choice. In a cooler room, or with a fan and an open window, 7.5 tog can suit the start and end of summer.
Is 10.5 or 13.5 tog better for winter?
Choose 13.5 tog if your bedroom falls below about 18°C overnight. Choose 10.5 tog if the room stays well heated or you tend to sleep warm. If you are between the two, a 10.5 tog duvet with a throw on top is easy to adjust.
Sources
- Tog (unit), Wikipedia)
- What duvet tog to choose: advice from bedding experts, Ideal Home
- Best summer duvets for keeping cool in the heatwave, Good Housekeeping UK
- Bedroom thermal conditions and their impacts on sleeping thermal comfort, PolyU
- Condensación en dormitorios: causas, soluciones y cuándo actuar
- Tenue cocooning pyjama : quelle matière choisir cet hiver
