Natural soy wax holds the most fragrance by weight at 8-10%. Some lighter fragrances can be added to soy wax up to 12%. This is almost twice the fragrance load of paraffin. Paraffin wax holds 4-6% fragrance by weight. Gel candle wax holds the least fragrance at 3-4% by weight.
Soy versus paraffin has always been the big debate for what wax holds the most fragrance. Paraffin wax technically holds less but the hot throw is often better.
Paraffin cures with a stronger cold throw and retains the fragrance longer resulting in a longer fragrance hot throw as the candle burns.
Soy wax has a reputation for easily releasing the fragrance oil, often through evaporation, resulting in a melt pool that lasts longer than the scent throw. Soy wax burns longer than paraffin.