There are no limits for third-party transfers. Larger transactions will lead to compliance asking additional questions on the transaction, but there is no upper limit.
Where third-party transfers are not available at all
Before the question of size, check whether third-party transfers are available to you at all.
If you are resident in the United States, Indonesia or the Philippines, your virtual account supports first-party transactions only, so the amount is not the deciding factor:
Indonesia and the Philippines: all third-party transactions are rejected and returned to the sender, at any amount, from individuals and companies alike.
United States: third-party transactions with another individual are not supported at any amount. Transactions with a company are unaffected and have no upper limit.
This is based on the country of residence recorded during your verification. For the full detail, see Third-party transfers: restrictions for the US, Indonesia and the Philippines.
For residents of all other countries, no upper limit applies.