It was widely reported that Baja California Sur in Mexico would introduce a tourist tax of $18 this month but local officials have confirmed that this contribution is not mandatory.

The state government of Baja California Sur - the southern tip of the Baja California peninsula - is requesting a voluntary contribution from visitors. The Los Cabos district in the south of the state has for decades drawn holidaymakers seeking sun-kissed beaches, surfing, whales, dolphins and excellent food. Every year, more than a million US tourists descend on resort cities like Cabo San Lucas and San José del Cabo, as well as the tiny beach town of La Paz.
Now it's hoping these visitors can contribute to sustainability of the state by donating money to the Baja California Sur Sustainability Fund.

Under the new voluntary program, visitors are invited to contribute 350 pesos or approximately US$18.50 at the San José del Cabo airport, if they're planning to stay in the region for more than 24 hours. Contributions can also be made online.
The fund will support public safety, health, education, housing, employment, sport, culture, agricultural and fisheries development and tourism and social infrastructure, Baja California Sur Govenor Carlos Mendoza Davis wrote on Twitter.
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Announcing the fund, he predicted the program would bring in 490 million pesos (about $25.5 million) in its first year.