Underneath "trc20 vs erc20" sits one idea: the coin is the same, the road it takes is not. USDT TRC20 is the version of USDT issued as a TRC20 token on the TRON blockchain, and it is one of the most common ways to send USDT because fees there are usually low. The same coin also exists as BEP20 on BSC and as ERC20 on Ethereum. Each version has its own fees and rules, and a balance on one network never moves to another by itself.
TRC20 vs BEP20 is mostly a question of chain and fee coin. TRC20 runs on TRON and pays its fees in TRX or through energy and bandwidth; BEP20 runs on BSC and pays them in BNB. Both are usually cheaper than Ethereum. Which is cheaper at a given moment depends on network load, the resources an account holds and the withdrawal charge an exchange adds. TRON addresses begin with T and BEP20 ones with 0x, yet the network should still be picked from the list at both ends.
TRC20 vs ERC20 sets TRON against Ethereum. ERC20 fees, paid in ETH gas, are often far higher when Ethereum is congested, which is why many people prefer TRC20 for small USDT amounts when the receiving side supports it. Support is the deciding detail: some platforms accept only one of the two, and some take a network for deposits but not for withdrawals, so each page needs its own check. On any route used for the first time, sending a small amount before the full sum proves that the network lines up.
A small first transfer costs one extra fee but shows that the network matches before the full sum moves.
A TRON address usually starts with the capital letter T, unlike the 0x addresses of Ethereum and compatible chains.
ETH, as gas: the gas the transfer uses times the gas price at that moment, which rises when Ethereum is busy.
Its network list for sending and receiving should name TRC20 or TRON explicitly; supporting USDT alone says nothing about the network.
Not reliably. Addresses on BEP20 and ERC20 share the 0x format and may match exactly, so the network is picked from the list and matched on the receiving side.