How to Write a When If Then Automation Rule

To write a when if then automation rule, you only need three lines. Line one names what happens. Line two names what you check. Line three names what the system does next. If you can write those three lines in plain words, you can build the rule in almost any tool.

The short video below introduces the same idea for an online store. This article is the worksheet version: how to draft your own rule, test it on paper, and spot the one line most owners skip.

What goes on each of the three lines?

• When: the event that starts the rule, such as a new order arriving.
• If: the check that decides what should happen this time.
• Then: the single action that follows when the check is true.

Write the lines in that order. Owners who start with the action usually end up with a vague wish, not a rule a tool can run.

Step 1: How do you write the When line?

Pick one event that already happens in your business every week. Keep it narrow and observable. A new order is a good When line because your store records it the moment it happens. A phrase like when business is slow is not usable, because no system can watch for it.

Good When lines name an event and nothing else. They do not include the decision and they do not include the response. Those belong on the next two lines.

A quick check for your When line

Ask: could a tool notice this event on its own, without a person judging it first? If yes, the line is ready. If no, make the event more specific until it can be noticed automatically.

Step 2: How do you write the If line?

The If line is the check, and it is the line that makes a rule feel personal instead of robotic. Without it, every customer who triggers the rule gets the exact same response.

Write the If line as a question with a clear yes or no answer. In the store example from the video, one trigger leads to three different checks: whether the order is large, whether it is a first purchase, and whether the item is available. Each check points to a different response.

Keep one check per rule at first. If you need two checks, write two rules. A rule you can read in one breath is a rule you can debug when it misfires.

Step 3: How do you write the Then line?

The Then line names one action that matches the check. For a large order, the action in the example is a personal thank you note from the owner. For a first purchase, it is a welcome message with a short starter guide. For an item that is not available, it is an honest delay note to the customer, plus a reorder note to the supplier.

Notice the pattern: the action changes because the check changed. Same When, different If, different Then. That branching is the whole skill, and you practice it by writing branches on paper before you open any software.

What does a finished rule look like on paper?

Use this fill in template for your first draft:

• When ______ happens,
• if ______ is true,
• then ______.

Then write a second branch for the same When line, with a different If and a different Then. Two branches are enough for a first rule. You are training yourself to think in conditions, not in one fixed message for everyone.

Example, in brief: when a new order arrives, if it is a first purchase, then send the welcome message. When a new order arrives, if the item is not available, then send the delay note and start the reorder. The wording is plain on purpose. Plain rules survive contact with real tools.

How do you test a rule before you build it?

Run three paper tests. First, the same message test: if two different customers would receive the identical action, your If line is missing or too weak. Second, the yes no test: can your If question be answered from data the tool already has, such as order value or purchase history? Third, the match test: does the Then action actually fit the If, or did you copy an action from another branch?

If a rule passes all three tests, building it is mostly data entry. If it fails one test, fix the wording, not the tool. Most broken automations are broken sentences first.

What this means for your business

Start with the trigger you handle most often, which for many stores is a new order. Draft one rule with two branches today, on paper, in under ten minutes. Build only that rule this week and watch how it behaves. Once writing rules in three lines feels normal, every later automation gets easier, because you are no longer guessing what the system should do. You have already written it down.

For the full explanation of the underlying formula, read the earlier guide linked below, then come back to this worksheet to draft your own version.

Frequently asked questions

How do you write a when if then automation rule?

Write three lines. When names the event that starts the rule, If names a yes or no check, and Then names the one action that follows when the check is true. Draft it on paper first, then build exactly those lines in your tool.

Can one trigger have more than one if?

Yes. One event can branch into several rules, each with its own check and action. A new order, for example, can lead to one action for a first purchase and a different action when an item is not available.

Why does skipping the If line feel robotic?

Without a check, every customer gets the same action, no matter their situation. Adding an If line lets the system respond differently to different customers, which is what makes the result feel personal.

How many branches should a first rule have?

Start with two branches for one trigger. Two is enough to practice conditional thinking and to test the rule, without making it hard to read or debug.

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