What kind of hair extension?
Which hair extensions last the longest?
Fusion extensions last the longest. However, the difference in products, brand name, maintenance, hair type, bonding quality, hair quality, the users hair quality, quality of the application will all factor in.
For top name brand fusion brands, such as Great Length, Hair Dreams, SoCap, Balmain, Keratip, Custom Blends, and some other with higher grade bonding, it can stay in your hair until you take them out. Great Lengths have said 4 to 6 months. But what are the consequences?
I say three months is how long they should be in. Yes, they will stay in your hair longer, even 9 months to a year, but your hair will grow out, and with that comes complications, such as matting and dreads above the bond that can be detrimental when it's time to remove your hair extensions.
How am I sure how long they might last?
I have done thousands of sets, literally. This what I have done exclusively for the last ten years. My experience has shown me that low grade bonding material will shed out fast. High grade bonding material will not come at all until it's taken out. Well, perhaps some may come out on their own. Pictures of hair extensions here.
After three months, the hair extension is growing out with the hair and it not close to your scalp anymore. Hairs can twist ender these, the longer it gets and make the extension begin to stick together and dread up. While some people can go 5 month successfully, it is usually because they have good hair to begin with, practice good maintenance, and have enough hair to still cover and hide the bonds.
People with thin, fine hair may barely make it to three months and may require maintenance to stretch it to three months.
After 4 or 5 months and the hair begins to dread, removing them takes longer or damage will start to happen. This is with fusion.
Hair Extensions will last three months. That is how long that the hair extensions I do should last. Maybe more. Maybe less. While indeed they could stay in much longer, I strongly advise against it.