---
title: "Buy two, get another product free for supplement brands"
description: "Buy two, get a different product free, for supplement brands on sourced costs: what the free product costs, and what it gives up on the buyers who would have paid for it."
url: https://offersuite.io/playbooks/buy-x-get-y-across-products-for-supplement-brands
updated: 2026-10-13
---

# Buy two, get another product free for supplement brands

Buy two, get a different product free, for supplement brands on sourced costs: what the free product costs, and what it gives up on the buyers who would have paid for it.

### Buy 2

Revenue $85.19 to contribution margin $44.25 (51.9%)

Revenue

$85.19

Cost of goods

−$20.94

Pick and pack

−$3.20

Extra picks

−$0.48

Shipping label

−$9.29

Card fee per order

−$0.30

Refunds

−$4.26

Card processing

−$2.47

Contribution margin

$44.25

1 declared kind costs nothing on this option

### Buy 2, get a travel-size bottle free

Revenue $85.19 to contribution margin $38.53 (45.2%)

Revenue

$85.19

Cost of goods

−$26.18

Pick and pack

−$3.20

Extra picks

−$0.96

Shipping label

−$9.29

Card fee per order

−$0.30

Refunds

−$4.26

Card processing

−$2.47

Contribution margin

$38.53

1 declared kind costs nothing on this option

Two units alone, with the second product paid for, and with it free, shipping charged

| Option | Customer pays | Shipping charged | Costs | Margin | Margin % | Conversion against buying 2 |
| --- | --- | --- | --- | --- | --- | --- |
| Buy 2 | $75.90 | $9.29 | $40.94 | $44.25 | 51.9% | — |
| Buy 2 and a travel-size bottle at $15.00 | $90.90 | $9.29 | $47.85 | $52.34 | 52.2% | — |
| Buy 2, get a travel-size bottle free | $75.90 | $9.29 | $46.66 | $38.53 | 45.2% | +14.8% |

Every figure is computed by the margin engine in Offer Suite's own code, in whole cents, from the costs below.

## What the numbers say

Buy two at $75.90, get a travel-size bottle free: a different product, one the store also sells, at $15.00. Against a buyer of two who takes nothing more, the free product costs $5.72 per order: its unit cost and one more pick.

Against a buyer who would have added it at full price, the offer gives up $13.81: the $15.00 they would have paid, less the card fee and the refund reserve on it. That order kept $52.34; with the product free it keeps $38.53.

To earn what selling two earns per visitor, it needs 14.8% more buyers. The offer pays when it moves one-unit buyers up to two, and costs most where buyers were already paying for the free product: choose one that few orders hold.

Nature's Sunshine's Subscribe & Thrive takes 25% off every subscription order and ships it free. [Nature's Sunshine, Subscribe & Thrive, read 23 September 2026](https://www.naturessunshine.com/subscribe-and-thrive)

## The cost structure, and where it comes from

|  |  |
| --- | --- |
| Price | $37.95, a bottle of supplements. [Nature's Sunshine homepage, read 23 September 2026](https://www.naturessunshine.com/) |
| Unit cost | $10.47. From the reported gross margin: “Gross margin in 2025 increased to 72.4% compared to 71.5% in 2024.” [Nature's Sunshine, fourth quarter and full year 2025 results, read 23 September 2026](https://ir.naturessunshine.com/news-events/press-releases/detail/267/natures-sunshine-reports-strong-fourth-quarter-and-full) |
| Pick and pack | $3.20 per order and $0.48 for each extra item. [Fulfill.com, 3PL pricing benchmarks (The Fulfillment Advisor 2025 survey of 600+ warehouses), read 23 September 2026](https://www.fulfill.com/3pl-pricing) |
| Shipping label | USPS Ground Advantage, commercial, Zone 5, by weight rounded up to the pound: 1 lb $9.29 · 2 lb $10.50 · 3 lb $12.12 · 4 lb $13.89 · 5 lb $14.53. Packed weight is an assumption: 0.5 lb per unit. [USPS Notice 123, USPS Ground Advantage Commercial, Zone 5 (effective 4 October 2026), read 13 October 2026](https://pe.usps.com/text/dmm300/Notice123.htm) |
| Card fees | 2.9% + $0.30 per order: Shopify Payments' online rate for a standard card on the Basic plan in the United States. Higher plans pay a lower rate, and premium cards a higher one. [Shopify's pricing page for the United States, online standard card rates, read 12 October 2026](https://www.shopify.com/pricing) [Rates by plan and country](https://offersuite.io/fees/shopify-payments/united-states) |
| Refund reserve | 5%, Offer Suite's default assumption for consumables. NRF's all-category figure for online sales is 19.3%, but consumables are rarely returned; use your own rate. |
| Gift | A travel-size bottle: unit cost $5.24, retail $15.00. A half-size bottle, costed at half the full bottle's unit cost. |

## The offer, as an agent writes it

An agent writes this offer as one document for Offer Suite's API, validated against the offer schema. Below is one option of it: what the buyer gets and the price it promises. Offer Suite checks with a real cart that checkout charges exactly the prices above.

**Show one option 2 options · excerpt**

```
{
  "key": "two-get-one-free",
  "display": {
    "title": "Buy 2, get a travel-size bottle free"
  },
  "lines": [
    {
      "role": "main",
      "quantity": 2,
      "purchase": {
        "type": "one_time"
      }
    },
    {
      "role": "gift",
      "quantity": 1,
      "purchase": {
        "type": "one_time"
      }
    }
  ],
  "pricing": {
    "promise": {
      "firstChargeCents": 7590,
      "renewalChargeCents": null
    }
  }
}
```

How Offer Suite validates, versions and publishes a document like this one: [offer documents](https://offersuite.io/features/offer-documents).

## Questions

### Is buy two, get another product free profitable for supplement brands?

On these costs, with a travel-size bottle as the free product, the order keeps $38.53, $5.72 less than two units alone. It is profitable while it brings buyers of two who would not have come.

### Which product should supplement brands give away?

One that costs little to make and that few buyers already pay for. Here it has a unit cost of $5.24 against a price of $15.00: free, it costs $5.72 on an order that would not have held it and $13.81 on one that would have paid for it.

## See what your own offers earn.

Offer Suite opens to Shopify brands a few at a time. Join the waitlist, or ask for a free profit audit of your past orders: realized profit per item and per offer option, what each costs you, and where margin leaks.

[Join the waitlist](https://offersuite.io/waitlist) [Request a free profit audit](https://offersuite.io/profit-audit)

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