The Kingdom of Swaziland only has around $790,000 left in the bank, according to the central bank's latest estimate, as an economic slowdown in neighbouring South Africa hits home.
The official reserves would cover only four months of vital imports, the central bank's Monetary Policy Consultative Committee said in its latest fiscal update on Monday.
"The contraction in the level of reserves was mainly on account of payment of government's external obligations," a statement said.
The country is highly dependent on imports and has seen exports hit by a slowing South African economy.
"The South African economy continued to notch sluggish growth rates and the outlook remain precarious," the statement said.
The absolute monarchy, ruled by King Mswati III, also faces losing duty free access to the US market over concerns about human rights.
Swaziland has a poor rights record, where pro-democracy activists are often detained and charged with terrorism.
Political parties have been banned in the country since 1973.
The IMF has urged "wide-ranging structural reforms" to attract foreign investors.