Buy 2 Get 3rd Free

When to use this

Use this template when you want a classic "buy two, get one free" mechanic on a product category – for example "buy 2 T-shirts, get a 3rd one free". It's the cleanest way to set up multi-group bundle promotions in Deducto, and the pattern generalises to any matched/unmatched pairing (e.g. "buy a shirt, get a tie 50% off").

How it works

This is an Item Group promotion with two item groups – one acts as a prerequisite ("buy 2"), the other receives the discount ("3rd free"). The two together form the promotion's trigger.

• Buy 2 Tees group – Category is one of [T-shirt], Quantity: 2. This group acts as a prerequisite: the promotion can only fire if two T-shirts can be allocated to it.
• Get 3rd Tee Free group – same conditions as the first, but Quantity: 1. This is the group that actually receives the discount.
• Percentage action at 100% – applied to Get 3rd Tee Free only. Because the prerequisite group is not selected as a Target Item Group, its T-shirts stay at full price.
• Batch Limit: 1 – only one set of three T-shirts is discounted per cart. Adjust this to allow multiple bundles per cart.
• Lock Affected Items: Yes – the free T-shirt can't be doubly discounted by another promotion.

For the underlying concepts see Trigger Conditions, Item Groups, and Promotion Action in Creating a Promotion.

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The trick that makes this work

Both item groups must exist for the promotion to apply, but only the second is targeted by the action. The first group acts purely as a precondition – its items have to be in the cart but they don't receive the discount. This decoupling is what lets you mix conditions across groups: a "buy a shirt, get a tie 50% off" promotion uses the same shape, just with different conditions on each group.

Step-by-step setup

1. From your Deducto Dashboard, open the promotions list for your project and click New.
2. Choose Item Group as the promotion type.
3. On the General Information tab, set the name, schedule, and behaviour. The full set of values is in the field reference below.
4. On the Trigger Conditions tab, leave the conditions empty.
5. On the Item Groups tab:
   • Configure the default group:
     • Name it Buy 2 Tees.
     • Set Quantity to 2.
     • Add one condition: select Category as the attribute, choose is one of, then either use the Entity Searcher (if you have a search integration set up) to pick the T-shirt category, or use Bulk Add to enter the value directly.
   • Click Create New to add a second group:
     • Name it Get 3rd Tee Free.
     • Set Quantity to 1.
     • Add the same Category condition as the first group.
6. On the Action tab, choose Apply A Percentage Discount to Item Group(s), set Percent to 100, set Batch Limit to 1, and under Target Item Groups check only Get 3rd Tee Free. Leave Buy 2 Tees unchecked – this is the step that distinguishes a working promotion from one that gives away every T-shirt.
7. Click Save.

Variations

• Different category. Update both groups' Category condition to match your target category (Hoodies, Mugs, etc.).
• Different paired conditions. Set different conditions on each group to build cross-category bundles, e.g. Category equals Shirt on group 1 and Category equals Tie on group 2 for "buy a shirt, get a tie".
• Partial discount instead of free. Reduce Percent from 100 to e.g. 50 for "buy 2 get a 3rd 50% off".
• Multiple bundles per cart. Increase Batch Limit (e.g. 2 for two bundles), or set it to 0 for unlimited.
• Buy-3-get-4th-free, etc. Adjust the first group's Quantity to the number of paid items required.

Testing

1. Add one T-shirt to your cart and confirm no discount is applied.
2. Add a second T-shirt and confirm still no discount.
3. Add a third T-shirt and confirm one T-shirt becomes free.
4. Add a fourth, fifth, and sixth T-shirt and confirm only one set of three is discounted (because Batch Limit: 1).
5. Add a non-T-shirt item alongside and confirm it isn't included in the bundle.

Field reference

The full set of fields used by this template: