When a person says "I love you more" in a romantic context, it's typically a sign they want to increase their level of commitment to the relationship. That's why it's important to know how to respond when your partner makes that declaration. The best way to show them that you love them more is with actions rather than words. It doesn't have to be a huge grand gesture, but something as small as an embrace or a kiss can let your partner know that their words mean a lot to you.
There's no set timeline for when it's the right time to say "I love you more," but a few clues can help. For instance, it's likely too early to say those three words if you don't know your partner very well. The reason is that love requires a deep understanding of both someone's strengths and weaknesses. That type of knowledge can't be gained in a few dates or fabulous sexual encounters, as is often the case.
It's also possible to say those words too soon if you feel you love your partner because of the excitement of romance and not because of the deep connection you have with that person. That type of feeling is more akin to infatuation, which can quickly fade without a deep enough bond. It's better to hold off on those three words until you have a firm grasp of your partner's character. This will ensure that you aren't saying them to someone who may not reciprocate your feelings.