Flow versus Apex for business automation
Key Takeaway
Consider Flow first. When one step needs logic Flow doesn't handle well, such as complex validation across multiple objects, keep the flow running the process and have it call invocable Apex as an action.
Flow and Apex are the two main tools for automating business logic in Salesforce. Flow is a declarative, point-and-click tool you build in Flow Builder. Apex is a Java-like programming language that needs skilled developers to build, test and maintain. Both tools can query records, run conditional logic, and create, update or delete records. So the real choice is about performance, scale and long-term maintenance, not about whether a task can be done at all.
Start with Flow
Salesforce recommends considering declarative tools, such as Flow, before custom code. Flow automation is usually easier to build and support. Code-based projects are generally more expensive to build and maintain, and they need an Apex developer. Most common automation scenarios can be built in flows just fine.
Flow is the ideal choice for most teams. Admins can build and change flows faster than developers can write, test and deploy Apex. Flow is the go-to option for simple to moderately complex logic, including record-triggered updates to the triggering record and to related records. Flow is also the best fit for sending email alerts and outbound messages when records change.
Flow is the best fit for work at a future, dynamic date, such as 3 days before a close date. Scheduled paths automatically schedule, cancel and reschedule that work if the record's data changes. An Apex trigger cannot natively do this.
There is no simple, definitive rule for choosing flows or code. Trying a flow first and moving to code if it does not work out is a normal and acceptable approach.