They now can transfer up to 800,000 baht ($25,039) per day per customer, up from 200,000 baht previously, effective from Jan. 12, Assistant Governor Vachira Arromdee said in a statement.
The move, in accordance with the central bank's foreign exchange control reform adopted since mid-2017, will increase flexibility for individuals and small- and medium-sized businesses, she added.
The baht traded at 31.95 per US dollar, having risen by 2.1 percent so far this year after increasing 9 percent in 2017.
The strong baht has worried exporters, and the Bank of Thailand said last week it had acted when the baht was rising too fast to ease the impact on businesses.
Deputy Prime Minister Somkid Jatusripitak said on Monday the baht's strength has been driven by a weaker dollar but it was still moving in line with regional currencies.
The central bank is already "taking care" of the baht to pervent unusual moves of the currency, he said.
"Everyone faces the same problem. It's because of a weaker dollar as people lack confidence. It's not only the baht that is strengthening," he said.
"For Thailand, we will have to make everything better. The private sector has to adjust better."