Hasbro Monopoly:

For Monopoly editions made by Hasbro, the easiest method is to check the production code. The first four digits identify the month and year the edition was created (MM/YY). This includes Monopoly sets released under the Waddingtons or Parker brand after Hasbro acquired the company

Non-Hasbro Modern Monopoly

For non-Hasbro releases (e.g. Winning Moves), the best estimate of date will be the copyright year on the side of the box. Usually this will be the year that the edition was released. However, if the edition was released early in the year, the copyright may be from the previous year

Older Classic Monopoly

For older classic Monopoly sets, an estimate can be identified by looking at the copyright year. This may be on the box, board, or instructions. Use the latest year as pieces were made in bulk and reused in later editions – therefore a set may have many years. To make this year more accurate, look at minor changes to the box within that period. In Europe and USA, through the 1960s, many boxes are dated ©1961 despite slight differences.

Despite both being ©1985, the change from Parker Kenner to Tonka means this edition is more likely from 1987.

Within the UK (and some international releases), Monopoly was released under Waddingtons until the Hasbro acquisition in 1994. The Waddingtons and Parker brand continued to be used until the Hasbro brand became permanent in 2009

Branding for USA and many international releases:

1935Parker Brothers
1968General Mills
1985Kenner Parker Toys

Within Spain, classic editions of Monopoly were released by ‘Borras’ until Hasbro took over production permanently in 1996. Variants such as Junior, European & Playmaster were released during this period without Borras involvement.

1935 to 1950s (including World War II)

Finally, many different variations were released within the UK and USA during the 1930s to 1950s – especially due to shortages during the war. The best method of identification is comparing the boards, pieces and box to that of already dated sets (many examples within this website).

Examples of: