Guinea-Bissau Tyres 2026: Monsoon Rules, Not Winter

Guinea-Bissau has no winter, and its road rules contain nothing about winter tyres, studs or seasonal sidewall markings. The only tyre figure that carries any weight is tread depth, and the country does not publish one of its own online — 1.6 mm is the international benchmark, and it is the number this page works to.

What actually decides whether a tyre copes here is the monsoon. From June to October the rain is heavy and the drainage is not, and a tyre that is fine in the dry season becomes a passenger in the wet one.

Tyre Law Summary for Guinea-Bissau

Why the Seasons Here Are Wet and Dry, Not Warm and Cold

Guinea-Bissau runs from mangrove coast to low inland savanna, and its temperature range across the year is narrow. Summer tyre compounds work all twelve months. There is no point in the calendar at which a winter tyre would be the better choice, and no rule asking for one.

The standard European instruction — switch below 7 °C, look for an M+S stamp — does not apply anywhere in the country.

Tread Depth in Guinea-Bissau

Work to 1.6 mm as the floor, measured across the central three-quarters of the tread around the full circumference, taking the shallowest reading.

Change at 3 mm if you will be driving in the rains. Wet grip declines gently from a new tyre down to about 4 mm and then falls away sharply, so the last couple of millimetres cost far more performance than the first few. On a flooded road outside Bissau that is the whole margin.

What Happens if Your Tyres Are Illegal

A roadside check can produce a fine. The heavier consequence comes afterwards: if a collision is investigated and the tyres are below standard, fault and insurance both become much harder to argue.

Choosing Tyres for Guinea-Bissau

• Wet traction: frequent heavy rain and standing water make aquaplaning the primary risk. Open, wide grooves beat a quiet tread pattern here
• Heat and UV: rubber ages faster in this climate than in a temperate one. Check the DOT code and treat five years as the point to start watching a tyre closely
• Sidewalls: laterite and unpaved roads cut sidewalls. Reinforced sidewalls are worth paying for outside the capital
• Pressure: check monthly, always cold, before the day heats the carcass

Road Conditions and Tyre Wear in Guinea-Bissau

The paved routes out of Bissau are reasonable. Secondary and rural roads are not, and the difference appears quickly once you turn off.

Practical measures:

• Carry a full-size spare, not a space-saver, outside the capital
• Check sidewalls for cuts and bulges at the end of each day on unpaved roads
• Slow down on unpaved sections — stones and debris cause most punctures here, and speed is what drives them in

How Guinea-Bissau Compares to Its Neighbours

Guinea-Bissau has two land borders, Senegal to the north and Guinea to the south and east. Neither has a winter tyre rule, so a legal tyre stays legal across both:

• Senegal: no winter tyre rule, no studded category.
• Guinea: no winter tyre rule, no studded category.

What changes at those borders is paperwork, insurance and fuel, not tyres.

For speed limits, traffic rules, and licence requirements in Guinea-Bissau, see our Driving in Guinea-Bissau guide.