A late October morning, the thermometer outside the window shows a couple of degrees above zero, and the car is still on summer tyres. Change now, or hold out until 1 December, when the law requires winter tyres? Below is the answer in numbers: what deadlines and requirements apply in Latvia, what independent braking tests show about how summer tyres behave in the cold, and at what point a change genuinely pays off, even if there is no snow yet.
What the law in Latvia says: deadlines, markings, fines
From 1 December to 1 March, light vehicles with a gross weight of up to 3500 kg may be driven in Latvia only on winter tyres. Since 1 October 2024 a stricter marking requirement has also been in force: during the winter period, only a tyre bearing the "mountain and snowflake", or 3PMSF, symbol - which certifies a passed snow grip test under UNECE Regulation No. 117 - is recognised as a winter tyre. A tyre with only the M+S marking is no longer valid in winter - it may be used only from 1 March to 1 December.
- Tread depth in winter - at least 4 mm for passenger cars (Cabinet Regulation No. 295); 3 mm is enough for buses with a gross weight above 3.5 t, and 2 mm for lorries above 3.5 t.
- Studded tyres are permitted from 1 October to 1 May, and one car may not have studded and non-studded tyres fitted at the same time.
- On one axle the tyres must be identical - one manufacturer and one tread pattern.
- The fine for driving in the winter period without appropriate tyres is 30 EUR (Section 71 of the Road Traffic Law), and a car with non-compliant tyres will not pass the technical inspection either.
For comparison - Germany has no fixed dates: there, Alpine (3PMSF) tyres are mandatory only when there is snow, ice or slush on the road, and fines start at 60 EUR. Latvia's system is simpler, but the calendar knows nothing about the weather. That is why 1 December should be read as the final deadline, not the recommended moment to change.
+7 degrees or the first frosts - which is the real signal
Continental's official recommendation is to switch to winter tyres once the air temperature stays consistently below +7 °C: in the cold, the rubber compound of summer tyres hardens and the braking distance grows. This threshold is no magic number, though. In Tyre Reviews' independent temperature test at Finland's Test World track, where braking was measured at 0, 2, 6, 10 and 15 °C, tyre performance changed gradually - there is no sharp break point at +7 °C. The decisive advantage of winter tyres appears on snow, ice and cold wet surfaces, not in cold air alone.
In practice this means the morning frost matters more than the daytime temperature. CSDD reminds drivers that once the temperature slips below zero, roads ice over in places as early as the morning hours, and on a slippery surface the braking distance at 50 km/h can be up to three times longer than on a dry one. The authority itself urges drivers not to wait for 1 December. In Latvia such conditions usually arrive in late October or early November.
How many metres a summer tyre costs on snow
Here the numbers speak more clearly than any recommendation. In Auto Bild's 2025 winter tyre test (size 225/40 R18), the summer reference tyre stopped from 50 km/h on snow after 51.1 metres. The best winter tyre, the Kleber Krisalp HP3, managed it in 27.1 metres, and even the weakest winter tyre in the test, the Toyo Observe Winter Sport 1, stopped in 29.7 metres. For a summer tyre, the braking distance on snow comes out nearly twice as long, and the gap exceeds 20 metres.
On wet asphalt the picture is more nuanced. In the same Auto Bild test, braking from 100 km/h, the summer tyre needed 47.8 metres, the best winter tyre, the Goodyear UltraGrip Performance 3, 50.9 metres, and a budget-class winter tyre 70.5 metres. In the wet, a quality winter tyre gives up only three metres. The cheap one - more than 22 metres. When choosing between a dearer and a cheaper set, that difference means far more than the euros saved; we have written about this in more detail in our comparison of budget and premium tyres.
Why you shouldn't fit winter tyres too early
If winter tyres were better in all conditions, you could fit them in September and never take them off at all. The tests show the opposite. In Auto Bild's 2025 measurements on dry asphalt, the summer tyre stopped from 100 km/h in 37.8 metres, the best winter tyre, the Michelin Pilot Alpin 5, in 42.6 metres, and the Kleber Krisalp HP3 in 47.3 metres. In warm weather a winter tyre takes 5 to 10 metres longer to stop.
ADAC has demonstrated the same even more vividly: in summer, on dry asphalt, winter tyres stop from 100 km/h up to 16 metres further than summer tyres, and at the spot where a car on summer tyres has already come to a halt, one on winter tyres is still doing around 37 km/h. Add the cost argument - in warm weather the soft winter compound wears faster, so every warm month on winter tyres shortens the set's life. An early change is not a safety reserve. It is money and needless metres of braking distance.
Studded, studless or all-season - what the measurements show
In the 2025 comparison by Tekniikan Maailma and UTAC (205/55 R16), the best studded tyre, the Bridgestone Blizzak Spike 3, stopped from 50 km/h on ice in 32.3 metres, while the best studless tyre, the Kumho WinterCraft Ice, took 33.1 metres. The difference is less than a metre. The weakest studless tyre in the test, the Hankook Winter i cept IZ3, however, needed 53.5 metres - about twenty metres more than the class leader. On snow from 80 km/h the two classes were practically equal: 49.5 metres versus 49.8. A simple conclusion follows from these numbers: the quality of the tyre means more than the presence of studs.
So who needs studs at all? Nokian puts the choice simply: studded tyres are for those who often drive on icy country roads or packed snow, and for less experienced drivers; studless tyres are quieter and better suited to driving mainly on maintained highways and in the city. Studded tyres may also be fitted as early as 1 October, so their owners can change tyres early and avoid the queues at the workshops. An overview of the available models can be found in the studded winter tyres section.
All-season tyres were long regarded as a compromise, but the latest tests are correcting that picture. In Auto Zeitung's 2024 test (215/55 R17), the best all-season tyre, the Bridgestone Turanza All Season 6, stopped from 100 km/h on dry asphalt in 38.3 metres - 6.6 metres shorter than the weakest winter tyres. On snow from 50 km/h, the best winter tyre, the Vredestein Wintrac Pro (21.7 m), beat the best all-season tyre, the Goodyear Vector 4Seasons Gen 3 (22.2 m), by just half a metre. For a city driver with a low annual mileage, a quality all-season tyre with the 3PMSF marking is a legal and practically sound alternative to two sets; most of the all-season tyres in our tyre catalogue carry this marking.
A five-minute check before the season
Before the tyres travel from the cellar to the workshop, it is worth spending five minutes on a check - it can save you one unnecessary trip.
- Tread. The legal minimum in winter is 4 mm; for comparison, a new winter tyre has around 10 mm of tread according to Continental's data. A tyre approaching the 4 mm limit should be replaced before the season, because its snow grip has already dropped noticeably by then. ADAC considers 4 mm the safety threshold even where the law demands less.
- Age. The DOT code on the sidewall shows the week and year of manufacture. CSDD advises against using tyres older than 5-6 years, and ADAC recommends replacing winter tyres after 6 years at the latest - the rubber hardens even if the tread looks good.
- Marking. The sidewall must carry the 3PMSF symbol; M+S on its own is no longer valid in the winter period.
- Fitting time. Around the first frosts and 1 December, queues form at the workshops, so it is better to book in good time. After the change, check the pressure in cold tyres, and after roughly 100 km retighten the wheel bolts.
CSDD's historical data show just how relevant the tread check is: in a summary published in 2016, around 7% of the passenger cars checked at the technical inspection over a single winter season - more than 10,000 - were driving on tread below the mandatory 4 mm.
Summary: when to change tyres
Winter tyres should go on when the average daily temperature stays steadily below roughly +7 °C and morning frosts are expected - in Latvia that usually means late October or early November. The first of December is the legal boundary with a 30 EUR fine beyond it, not a target date. In spring the logic is the same, only in reverse: the law no longer requires winter tyres after 1 March, but March in Latvia still regularly brings morning ice, so it is wiser to switch back to summer tyres once the nights no longer bring steady frost. And one more CSDD reminder to finish: even on good winter tyres, the braking distance on an icy road can be up to three times longer than on a dry one, so speed and following distance must be adjusted to the conditions, not the calendar.
