Motorists are gearing up for the new autoroute vignette.
The annual permit costs 40 francs and will be required from February next year.
But discount retailers are sparking a price war. Lidl is offering the sticker for as low as CHF 19.90 francs, if shoppers spend at least CHF 70 and use its app.
Aldi is countering with a CHF 24 offer under similar spending conditions.
And Denner is sticking to its long-running approach, giving buyers a CHF 10 voucher with a 100-franc shop.
All offers are limited, but perfectly legal, as retailers buy vignettes at full price and absorb the discount to lure customers.
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