Thailand's political upheaval may be driving tourists away, but they're likely to rush into the waiting arms of some neighboring countries, Credit Suisse said.
The tourism sector has already taken a hit, with the key December high season seeing a slim 6.7 percent on-year growth in arrivals, compared with a more than 30 percent climb in December 2012, while the number of tourists coming from Hong Kong actually dropped nearly 27 percent for the month, according to data from the Department of Tourism.
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The street protests began in late October of last year, but the size and level of disruption to the capital city has increased since the start of this year.
"History shows that tourists from China and Hong Kong have been the most sensitive to political turmoil and natural disasters," the note said, adding that this group now accounts for around 20 percent of total visitor arrivals. "Data for December 2013 already showed a collapse in Chinese and Hong Kong visitor arrivals, even before the current political crisis intensified earlier this year."
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"If political instability lasts for most of this year, the volume of visitors may stay roughly flat in 2014 versus a projection of 7.5 percent year-on-year growth earlier," the bank said in a note.
But Thailand's bane could become a boon for some of its neighbors.
"History suggests Malaysia, and to a lesser extent Indonesia, generally benefit from the substitution effects, while Singapore appears to suffer from complementary effects from a negative tourism shock in Thailand," Credit Suisse said.
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"Thailand and Malaysia's relative tourism growth tend to move in the opposite direction," it said, with Malaysia outperforming the region whenever Thailand's tourism sector experiences negative shocks in most cases. The correlation with Indonesia is slightly lower, it noted.
Another factor likely to bolster Malaysian arrivals is the planned "Visit Malaysia Year" campaign this year.
"VMY tends to give a large boost to tourism arrivals in Malaysia, with over 200 events organized," it said. Previous campaigns in 2007, 1994 and 1990 pushed up arrivals by 19 percent, 11 percent and 54 percent respectively, compared with arrival growth of 4 percent in 2013. The three previous VMY events also appeared to dent Thailand's market share, it noted.
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Credit Suisse is raising its forecast for Malaysia's economic growth this year to 5.3 percent from 5 percent, partly due to the combination of tourists siphoned from Thailand and the VMY campaign.
Not all of Thailand's neighbors will benefit. Singapore may suffer a one-two punch from the VMY campaign, which historically has hurt arrivals to the city-state, and the Thai turmoil, Credit Suisse said. However, it noted the impact on economic growth and its current account should be limited.
—By CNBC.Com's Leslie Shaffer; Follow her on Twitter @LeslieShaffer1