The reply paywall will prevent unverified accounts that do not pay for X Premium from engaging in discussions on certain posts.
It is the latest change to the platform that Mr Musk has overseen since taking over Twitter last year and renaming it X.
The tech billionaire, who is the most-followed person on X, said the latest limits “should help a lot with spam bots”.
Mr Musk has brought about a complete overhaul of the way verification on the platform works since his takeover, removing the legacy blue ticks from celebrities, journalists and politicians, and giving them to anyone who paid a monthly subscription fee.
These paying users were also given prominence over non-paying users when appearing in searches, as well as prioritised ranking in conversations.
The move comes amid reports that Mr Musk is planning to test new subscription options for X users, which could see the introduction of up to three tiers.
Each premium tier will offer different levels of ad exposure, according to a report in Bloomberg, though it is not clear if the price of the top tier will differ from the $11 (£9.60) that it currently costs.
Monthly fees for Meta’s platforms, which include Facebook and Instagram, could cost between €10 (£9) and €13 in Europe, The Wall Street Journal reported last week, and come in response to Europe’s data privacy laws.
These laws are seen as a threat to the lucrative business model of showing personalised ads to users, with a spokesperson confirming that Meta was exploring options to “comply with evolving regulatory requirements”.
https://www.independent.co.uk/news/elon-musk-ap-philippines-new-zealand-london-b2431687.html X introduces limits to prevent non-paying users from replying to posts