The company's Spanish subsidiary, Coca-Cola Iberian Partners, plans to shutter its plants in the northwestern Asturias region, the Balearic Islands, near Madrid and in southeastern Alicante, the union said in a statement.
UGT said it was seeking to negotiate with Coca-Cola to head off the closures, and would launch strikes and demonstrations to press its position.
The company, in a statement published in Spanish media, said it would try to place 500 of the affected workers in other positions, and offer the rest early retirement or attractive termination packages.
"The restructuring aims to gain efficiency and competitiveness, and to avoid duplication that could compromise the future viability of the company," it said.
Coca-Cola Iberian Partners, which currently has 4,000 employees on its books, was founded last year by merging the seven bottling companies in Spain owned by the US brand.