Lottery promotions in the form of discounts on lottery tickets are specified in Clause 2, Article 42 Circular 75/2013/TT-BTC as follows:

Information, advertising and promotions in lottery business activities

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2. Lottery promotions.

Lottery companies, Vietnam Lottery companies and related organizations and individuals are strictly prohibited from conducting lottery promotions in the following forms:

a) Reduce the selling price of lottery tickets;

b) Giving away lottery tickets without collecting money;

c) Giving gifts in the form of in-kind, money or vouchers or service vouchers so that customers can enjoy one or a number of certain benefits;

d) Increase the value of the prizes compared to the prize participation rules and reward payout rates according to state regulations;

d) Selling lottery tickets with participation in prize programs;

e) Other forms of promotion.

Thus, according to the above regulations, lottery companies are strictly prohibited from conducting lottery promotions in the form of reducing the selling price of lottery tickets.