(Adds comment, detail on inflation)
By Helen Murphy and Nelson Bocanegra
BOGOTA, Oct 30 (Reuters) - Colombia's central bank held its benchmark interest rate steady on Thursday, meeting market expectations, as benign inflation allows policymakers to maintain economic stimulus while global conditions remain uncertain.
The seven-member board voted unanimously to maintain the rate at 4.5 percent, as predicted by 31 of 32 analysts forecast in a Reuters poll. It was raised to that level in August after a series of quarter-point hikes that began in April.
The bank has expressed concern over the global economy, highlighting how other nations could impact Colombia. Analysts now expect the bank to hold the rate at least through year end.
"New projections for world economic activity for the remainder of 2014 and 2015 suggest that the average growth of our business partners will be less than estimated earlier," the board's statement said.
"External demand will be driven mainly by the U.S. economy, while low dynamism is expected in the Euro zone. China will have a slowdown, and some partner countries in the region will grow at less than their average rates of recent years."
The bank narrowed its forecast range for 2014 GDP growth to between 4.5 percent and 5.5 percent versus 4.2 percent to 5.8 percent previously. It kept its estimate for probable growth unchanged at 5 percent.
Economic growth in 2015 will likely be lower than this year but probably remain above 4 percent, bank chief Jose Dario Uribe said.
The U.S. Federal Reserve on Wednesday ended its bond purchase program, a show of confidence its economy is on the mend. While U.S. rates are expected to remain low for some time, improvement in its economy will help bolster Colombian growth.
The sharp fall in crude oil prices this quarter has cut revenue from taxes and royalties in the Andean nation, causing concern from policymakers and prompting the government to present a tax reform that would replace those missing funds.
"Be assured that the fiscal stimulus we have been giving until now will be maintained next year, because corporate results this year are those which will determine fiscal income in 2015," said Finance Minister Mauricio Cardenas, who votes on the board.
Inflation in 2014 is forecast at slightly higher than the mid-point of the 2-4 percent target, well above a near 50-year low of 1.94 percent in 2013.
Last month, one member of Colombia's board voted to raise the rate to damp inflationary pressures that could come if economic expansion quickens in the coming months.
"Those thinking of a rate increase are probably more relaxed now with the current level," said Francisco Chaves, chief economist at Corredores Asociados.
Board member Carlos Gustavo Cano said on Oct. 8 that the rate could be left at 4.5 percent "hopefully for the longest time possible."
"With activity growing at what we believe is its potential, and with inflation expectations under control, the central bank should now be able to remain on hold for 2015," said Munir Jalil, chief economist at Citigroup Colombia. (Additional reporting by Peter Murphy; Editing by Alan Crosby and Richard Chang)