Registration of securities issued in business combination transactions

Cover

v3.21.2
Cover
6 Months Ended
Jun. 30, 2021
Cover [Abstract]  
Document Type S-4
Amendment Flag false
Entity Registrant Name COMMUNICATIONS SYSTEMS, INC.
Entity Central Index Key 0000022701
Entity Tax Identification Number 41-0957999
Entity Incorporation, State or Country Code MN
Entity Address, Address Line One 10900 Red Circle Drive
Entity Address, City or Town Minnetonka
Entity Address, State or Province MN
Entity Address, Postal Zip Code 55343
City Area Code (952)
Local Phone Number 996-1674
Entity Filer Category Non-accelerated Filer
Entity Small Business true
Entity Emerging Growth Company false