Under normal circumstances, online signing has certain legal effect, but it is best to sign a paper contract after online signing to ensure the validity of the contract. However, there are also special circumstances. For example, after the online signing, both parties actively fulfilled their contractual obligations, and this online signing has the final effect.

According to the provisions of China's Electronic Signature Law, the only online signing with legal effect means that both parties use electronic signature technology (each using a digital certificate issued by a third-party electronic certification body) to sign an electronic contract and other signing agreements online. At present, the third-party electronic signing platform that can provide online signing service in China is only the CA trading network approved by the state.