What is the difference between wet glue and self-adhesive labels?

The main difference is how the adhesive is applied: wet glue labels arrive as plain paper and are glued to the container by the labelling machine using water-activated glue, while self-adhesive labels come with adhesive pre-coated under a release liner that is peeled away just before application.

Wet glue is generally more cost-effective per unit at high volumes and is well suited to smooth glass containers, but it requires dedicated wet-glue application equipment on the packaging line. Self-adhesive labels apply with a standard pressure-sensitive labeller, work across a much wider range of substrates including plastics and metal, and support faster changeovers between SKUs, which makes them more flexible for shorter or more varied production runs.

The selection factors are container material, production volume, existing labelling equipment, and desired finish. A high-volume glass bottling operation, such as a distillery or brewery, often favours wet glue for its classic paper look and lower material cost at scale. A brand producing across multiple container materials, running shorter batches, or needing quick artwork changes between runs typically favours self-adhesive for its versatility. Some brands use both formats across different SKUs within the same portfolio, depending on each product’s container and volume profile.