How does MongoDB handle transactions?

Updated May 1, 2026

Short answer

MongoDB supports multi-document ACID transactions since version 4.0.

Deep explanation

Transactions allow you to group multiple operations. If one fails, the whole set is rolled back. They work across replica sets and sharded clusters.

Real-world example

Transferring money between two user accounts (debit one, credit another).

Common mistakes

Using transactions for everything, which can severely impact performance.

Follow-up questions

What is the default transaction timeout?

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