The subscription service is well known for hosting sexual content while allowing various creators to provide content to their fans.
And last May, the UK's government-approved regulatory and competition authority voiced concerns the platform should be doing more to prevent those under the age of 18 from accessing adult material.
In its summary, Ofcom said: "We are investigating whether OnlyFans has contravened its duties to implement appropriate measures ... to protect under-18s from encountering restricted material such as pornography.
"We are also looking at whether OnlyFans failed to provide complete and accurate responses to statutory information requests."
OnlyFans had told BBC that it experienced a technical issue but highlighted that it "works closely" with the regulator to "implement and develop best-practices on online safety".
A spokeswoman told the outlet "coding configuration issues" had affected some of the site's "age thresholds".
However, the organisation insisted those thresholds were always over 18.
In the statement, they added: "OnlyFans discovered the reporting error and proactively amended our report to Ofcom."
The investigation has now been dropped, though Ofcom will continue working with the platform to ensure they are doing everything they can to prevent children accessing the explicit content.
It said: “Where appropriate, Ofcom’s supervision team will continue to engage with OnlyFans around the way it implements measures to protect children from restricted material.”
OnlyFans' spokesperson commented: “We welcome today’s decision from Ofcom.
“Since 2021, OnlyFans has used the Government-approved age-assurance provider Yoti to check that UK fans are over the age of 18. At all times OnlyFans’ age assurance was set to at least 20 years old.
“OnlyFans is, and has always been, confident that these measures are sufficient to meet our obligations to protect under-18s from accessing restricted material.”