Infant Formula vs. Follow-On Formula: What’s the Difference and Does Your Baby Need Stage 2?

What Is Infant Formula (Stage 1)?

Infant formula, also known as Stage 1 formula, is designed to meet all the nutritional needs of healthy babies from birth up to 12 months of age.

All infant formula products are nutritionally suitable for the entire first year. However, many brands also offer a follow-on (Stage 2) formula and recommend switching to it from around 6–12 months.

What Is Follow-On Formula (Stage 2)?

Follow-on formula, or Stage 2 formula, is intended for babies aged 6–12 months.

It is often very similar to the same brand’s Stage 1 infant formula, with only small changes to nutrient levels or ingredients. If you’re thinking about switching, it’s worth comparing the nutrition information and ingredient lists of the two products to see exactly what’s different.

Not all brands offer a follow-on formula. Many parents assume Stage 2 products always have more iron or extra nutrients, but regulations do not require this—though some brands do add more iron. Always check the nutritional panel and ingredient list before making a decision.

Do You Need to Switch to Follow-On Formula at 6 Months?

Some brands may make small changes to their follow-on formula to suit babies aged 6–12 months, and will encourage parents to switch. However, there’s no essential nutritional requirement to do so. For most babies, continuing with Stage 1 formula until 12 months is perfectly fine—it’s entirely your choice.

Can I Feed Stage 2 Formula to a Baby Under 6 Months?

This question often comes up if a Stage 2 product is bought by mistake or if Stage 1 is out of stock.

The regulations for infant formula and follow-on formula are the same in most areas of composition, with over 100 detailed requirements. While there are some small differences, the two can actually have identical composition under current regulations.

For those interested, we’ve provided a technical summary of these differences below—but for most parents, speaking directly with the product’s customer service line or your healthcare provider is the easiest and most reliable approach.