Sweden, who have already returned home from the World Cup after being eliminated, were fined for the same offence prior to their quarter-final defeat to England.
The Swedish FA had confirmed at the time that it had received the sanction about its kit and socks.
"Despite having been previously requested to cease the activity that led to the breach and receiving a sanction on 6 July 2018, one member of the Swedish national team (as opposed to several players in the previous case) displayed unauthorised commercial branding on playing equipment items during the ... quarter-final match between Sweden and England," FIFA said.
World Cup finalists Croatia, who face France at Moscow's Luzhniki Stadium on Sunday, were also fined.
"A fine of CHF 50,000 and a warning to the Croatian Football Federation for breaching the Media and Marketing Regulations and the FIFA Equipment Regulations," FIFA said.
"In particular and despite having been previously requested by FIFA to cease the activity that led to the breach and receiving a sanction on 5 July 2018, one member of the Croatian national team displayed unauthorised commercial branding on playing equipment items during the ... semi-final match between Croatia and England," it said.
(Reporting by Karolos Grohmann; Editing by Toby Davis)
