The report is expected to recommend changes to the planning system to discourage supermarket chains from developing local monopolies.
It is likely to see a new competition test in which planners would consider a supermarket chain's local market share before granting planning permission.
In October, the Commission's provisional findings revealed around 200 areas of the country where consumers had little choice of where to shop.
It said: "A lack of competition in certain local markets not only disadvantages consumers in those areas but also allows retailers to weaken their offer to consumers nationally."
The Commission also found that of 520 landbank sites owned by supermarkets, more than a fifth were potentially being used specifically to stop rivals building competing stores.
Other proposals outlined in the October report, and which could feature in today's announcement included reviewing the planning system to allow greater scope for developments on the edge of town centres, while maintaining constraints on out-of-town supermarkets.