Yes, friends with benefits can say "I love you" to each other if they genuinely feel that way. The term "friends with benefits" typically refers to two individuals who have a casual, non-committed sexual relationship but maintain a friendship outside of the physical aspect.
While the relationship may not involve romantic commitment or exclusivity, it doesn't mean that deeper emotions can't develop. People are complex, and feelings can evolve over time. If both individuals in the friends with benefits arrangement have developed genuine feelings of love and care for each other, it's entirely possible for them to express those emotions.
However, it's essential for both parties to communicate openly and honestly about their feelings to avoid misunderstandings or unmet expectations. If one person is developing stronger feelings than the other and desires a more committed relationship, it's crucial to address these feelings and potential changes in the dynamic early on.
Every situation is unique, so what works for one pair of friends with benefits may not work for another. Communication and mutual understanding are vital to navigating any kind of relationship, even those that are more casual in nature.