There is none that I can think of.

The difference is rhetorical. The expressions sound different but their meanings are the same. "Day to day" emphasizes the sequential nature of one day after another, each day following the previous one in progression. "Daily" has the same meaning but does not call attention to the sequential progression of time. Here is a situation where "day to day" would work well but "daily" would not: "Billy did not like his new school. The teachers were strict and most of them were boring. In his day to day life, he dreaded going to school each morning because he would anticipate yet another bad time at school." "Day to day" is better than "daily" because it emphasizes the ceaseless progression of one bad day after another.

"Day-to-day life" and "daily life" are often used interchangeably, but there are subtle differences: 1. Day-to-day life: This phrase emphasizes the routine and ongoing nature of someone's life. It suggests a focus on the regular, repetitive aspects of life and how they are managed over time. * Example: "In his day-to-day life, he balances work, family, and hobbies." 2. Daily life: This phrase is more straightforward and refers to the activities and experiences that occur every day. It can be used to describe typical daily routines. * Example: "Her daily life includes exercising, working, and spending time with family." In essence, "day-to-day life" may carry a slightly broader or more dynamic implication, highlighting the management of routine over time, while "daily life" tends to focus on what happens each day. However, in many contexts, they can be used interchangeably without much difference in meaning.

Day-to-day life is how you live going from one day to the next, day after day. Daily life contains the word ''daily'', which means of or relating to the day. Therefore, Daily life means how life is like in a day. I think that both are very similar and could be synonyms.