If you build on Salesforce long enough, you’ll meet the question everyone asks sooner or later: Salesforce Flow vs Apex—what should I use? There isn’t a single answer for every org. Flow gives you speed and approachability. Apex gives you precision and power. The best teams treat them as complementary tools and make a deliberate choice based on the problem in front of them. What Flow does well (and where it struggles) Flow is the fastest way to ship business automation. Record-Triggered Flows react to creates and updates, Screen Flows guide users through forms, and subflows help you reuse logic. Admins can read, tweak, and version them without a deployment pipeline. Where Flow bends is where complexity and volume creep in: many branches, nested loops, heavy lookups across multiple objects, or tricky integrations with custom headers and signing. You can still deliver, but the Flow can become hard to reason about and may bump into governor limits sooner than you think. Where Apex shines Apex is code, and with code you get structure: classes, services, tests, clear error handling, and full control of queries and DML. It’s built for high-volume operations, advanced integrations, and transactional rules that must be executed in a precise order. The trade-off is time and the need for developer discipline. The quick comparison (at a glance) FactorFlowApexBuild speedFastSlowerMaintainability by adminsHighLowerComplex branchingLimitedExcellentHigh-volume dataRiskyStrongTransaction controlBasicFullAdvanced integrationsLimitedFullTestabilityBasicRich & enforced A practical way to decide Start from the user story, not the tool. If the requirement can be explained in a short paragraph—“when a Case priority becomes High, notify the team and set a target time”—Flow is usually the right first attempt. As the story accumulates edge cases—“except for VIP customers, except during change freezes, split by product and region, with a weekly digest and API callouts”—you’re drifting into Apex territory or a hybrid. A sensible hybrid pattern is: orchestrate in Flow, offload the heavy lifting to Apex via Invocable Actions. That keeps admin-friendly configuration while giving you reliable, bulk-safe logic. A worked example: lead qualification that grows up Imagine a simple lead qualification: When a Lead is created, assign it to a queue and create a follow-up Task. If the email domain matches a known customer, route to Account Owner instead. This starts beautifully in a Record-Triggered Flow: one Get Records, a Decision, two Assignments, and one Create. A month later, marketing adds scoring rules, product-based routing, do-not-contact checks, and an external enrichment service. Now the Flow carries five decisions, two loops, and a callout. It still works, but it’s harder to test and easier to break. Refactor the heavy bits: Keep the Flow to detect the event and orchestrate steps. Move scoring, enrichment, and routing into Invocable Apex that takes a collection of Leads, queries once, applies rules with Maps/Sets, and returns results in bulk. The Flow handles user-visible messages and updates; Apex handles efficiency, error logging, and retries. You’ve preserved agility without sacrificing reliability. Performance and limits (the stuff that bites) Salesforce enforces governor limits to keep everyone polite on multi-tenant infrastructure. In practice: Minimise loops in Flow; prefer operating on collections and doing one Get Records per object. In Apex, bulkify everything: gather IDs, query once, work in memory with Maps/Sets, do as few DML statements as possible. Be mindful of the order of execution. Recursive updates can fire more automation than you expect; use guards and “before vs after” triggers correctly. Testing and resilience Flow now has native testing features; use them for the happy path and at least one failure path. Add Fault connectors that surface actionable messages. Apex requires tests—treat that as a gift. Use @testSetup for data, assert behaviour (not line counts), and mock callouts. Good tests are your change-management parachute. Security considerations Flow respects CRUD/FLS by default. Apex must be explicit: choose with sharing wisely, and protect fields and objects using platform security helpers. Whichever tool you choose, log meaningful errors and avoid swallowing exceptions—you’ll thank yourself later. When to revisit your choice Re-evaluate when a Flow grows hard to read, runs close to limits, or hides logic in many places. Likewise, if an Apex trigger balloons into hundreds of lines with conditionals that look like a policy document, move business rules to Custom Metadata and expose simple, well-named Invocable operations for Flow to call. Clarity beats cleverness. A few questions people ask Is Process Builder still an option?It works, but Salesforce’s strategic direction is Flow. Build new automation in Flow and migrate when practical. Can Flow do callouts?Flow supports HTTP callouts. When you need complex authentication, request signing, or robust retries, Apex remains the cleaner approach. What about long, human-driven processes?Flow (including Orchestration features) is a good fit for multi-step user journeys. For back-end, compute-heavy work, consider Platform Events and asynchronous Apex. The balanced takeaway Use Flow to move fast and keep logic visible. Use Apex when the org needs power, precision, and performance. Most mature implementations land in the middle: Flow sets the stage, Apex plays the difficult solos. If you keep that mental model, your automations will stay understandable today and maintainable a year from now. Another key factor is any customisations stray away from the standard update path that Salesforce pushes 3 times a year. Salesforce makes frequent updates to the system, granting access to new functionality, and fixing bug with each release. When you start to produce custom code, you start to move away from Salesforce's intended functionality, meaning you will likely be missing out on these updates. This should also be a key consideration.