4 weeks is the longest we allow between refills without adding an additional charge to the appointment.
Why you ask?
When you come in for a refill, your artist needs time to remove the lashes that have grown out crooked and the lashes that have grown out 2mm or more from the lash line. These all must be removed before the refill can start.
We then need to even out both sides, fill in the gaps and inner and outer corners. As soon as we get both eyes even we then have to recreate the shape! Some people will ask "but I only want natural lashes. Why do I need to come in for refills so often?"
Same reason, we need time to recreate what you left with last time. Natural or dramatic, the steps are still the same. Natural means that the fans or classic lash are smaller or lass dense to give a natural look.
The longer you go in between appointments, the more growth you have and more lashes will need to be removed and replaced. it takes more time to do that and apply to the new growth.