The approval means the rival French and Swiss materials giants can go-ahead with a series of planned major disposals, including the Lafarge Tarmac business in the UK.
This was put up for sale in the summer, with the exception of its Cauldon cement works in Staffordshire which is being kept, with a price tag of around £1.4bn.
In the UK, Holcim owns Aggregate Industries, which boast a network of aggregate, asphalt, ready-mix and concrete products sites but presently imports cement.
Since unveiling plans for the merger in April, the Swiss and French groups have developed plans to offload at least £5bn of worldwide assets to win approval from multiple competition authorities.
Holcim and Lafarge will only be permitted to complete the deal once the Commission has approved the buyers.
Bruno Lafont, designated CEO of the future combined company, said: “We are very pleased with the positive decision of the European Commission.
“It also reflects the quality of the preparatory work performed by both teams so far in creating the most advanced company in our industry.
“With this decision, we remain firmly on track for a closing
in the first half of 2015.”