How Long Does Invisalign Take? Realistic Timelines by Case Type
Written by Dr Ali El-Kabengi BChD (GDC 270807), principal dentist at Toothi London · Last reviewed 25 September 2026
It depends on how far your teeth need to move. Across our three published tiers, Invisalign Go Express takes typically around 3 months, Invisalign Go typically around 6 months and Invisalign Go Plus typically around 9 months. Those are averages, not promises — the single biggest factor is how far your teeth need to move, which decides how many aligners are in your plan; the second is how consistently you wear them. Genuinely complex bite cases are quoted after assessment and referred on.
This guide explains what decides your timeline, what a typical course looks like week by week, why refinements can add a couple of months, and what you can genuinely do to finish sooner. The figures are averages from adult cases treated at our clinic in Edgware, North London, and every case is different.
Average Invisalign treatment times
| Case type | Aligners in the plan | Average time | Toothi tier |
|---|---|---|---|
| Relapse after childhood braces | 5–7 | typically around 3 months | Invisalign Go Express £1,495 |
| Mild crowding or a small gap | 5–7 | typically around 3 months | Invisalign Go Express £1,495 |
| Moderate crowding or spacing | 10–20 | typically around 6 months | Invisalign Go £2,495 |
| Crowding with rotations, both arches | 20–26 | typically around 9 months | Invisalign Go Plus £2,995 |
| Complex bite correction | 26+ (unlimited) | Assessed individually | Quoted after assessment and referred on |
Times shown are averages and vary from patient to patient. They assume aligners changed every 7 days and worn 20–22 hours a day, before any refinement stage. Costs are Toothi London’s published fixed fees — see our Invisalign cost UK guide.
What actually decides your timeline
- How many aligners are in your plan. Each aligner moves your teeth a fraction of a millimetre. Your dentist’s digital plan (the ClinCheck) sets out exactly how many aligners are needed to get from where your teeth are to where they should be. A 7-aligner plan is a 7-week plan; a 26-aligner plan is 26 weeks. This is fixed at the planning stage, and you will be told the number before you start.
- How often you change aligners. Most adults now change every 7 days. Some movements — rotating a canine, or intruding a tooth — are slower and your dentist may ask you to hold certain aligners for 10 or 14 days. Do not shorten the interval yourself: teeth that are moved before the bone around them has remodelled do not stay put.
- How many hours a day you wear them. The plan assumes 20–22 hours a day. At 16 hours the teeth lag behind the aligners, the aligners stop fitting, and you end up needing refinements. This is the factor most within your control and the one most people underestimate.
- Whether you need refinements. Roughly a third of cases need a second, shorter series of aligners at the end to finish the last details. This adds 4–12 weeks. It is normal, it is planned for, and at Toothi refinement aligners are included in the fee on all three tiers.
- How your teeth respond. Bone remodels faster in younger adults and slower in older ones; it is also slower if gum health is poor. Your dentist will factor this in.
A typical Invisalign course, start to finish
Consultation & scan
Examination, X-rays where needed, iTero 3D scan and an on-screen simulation. About an hour. You leave knowing the tier, the likely number of aligners and the fixed fee.
Planning & manufacture
Dr Ali designs your tooth movements digitally and approves the plan. Align Technology then makes your full series of aligners. Expect 2–3 weeks from scan to fitting.
Fitting
Attachments (small tooth-coloured bumps) are bonded on where needed, your first aligners are fitted and you are shown how to wear, remove and clean them.
Active treatment
Change aligners weekly as directed. A short review every 6–8 weeks checks the teeth are tracking. Most people see visible change within the first 4–8 weeks.
Refinements (if needed)
A new scan and a short second series of aligners to perfect the last details. Included on all three tiers at Toothi.
Whiten & retain
Attachments come off, teeth are polished, you have your Airflow hygiene clean and Boutique whitening, and your removable and fixed retainers are fitted. Retainers are for life — nights only after the first few months.
Can you speed Invisalign up?
Within limits. You cannot make bone remodel faster than biology allows, but you can avoid the things that make treatment slower than planned:
- ✓ Wear them 22 hours, not 20. Take them out to eat and brush, then straight back in. Every hour out is an hour the teeth are not moving.
- ✓ Use aligner chewies. A few minutes of biting on the soft foam cylinders after putting in a new aligner seats it fully, so the movement built into that aligner actually happens.
- ✓ Change on time, not early. Switching early feels like progress but causes tracking problems that cost you weeks later.
- ✓ Keep your review appointments. A tooth that stops tracking is easy to correct if caught at week 6, and hard if caught at week 20.
- ✓ Do not lose aligners. A replacement takes 1–2 weeks to arrive. Keep the case in your pocket, never wrap them in a napkin.
Some clinics offer vibration devices or photobiomodulation to accelerate movement. The evidence for meaningful time savings is weak, and we do not sell them.
Is Invisalign faster than braces?
For mild-to-moderate cases, Invisalign is usually as fast or faster — a 6-aligner relapse case finishes in weeks, where fixed braces would still need several months of adjustment visits. For complex bite cases fixed braces can be quicker, because they apply continuous force and can make some movements aligners find difficult. The honest answer depends on your teeth; see our full Invisalign vs braces comparison.
More Invisalign guides
Treatment time FAQs
How long does Invisalign take for mild crowding?
Mild crowding of the front teeth is usually an Invisalign Go Express case, which takes typically around 3 months. It typically needs 5–7 aligners, changed weekly, sometimes followed by a short refinement stage. This is an average, not a promise.
How long does Invisalign take for adults?
Most adults need Invisalign Go, which takes typically around 6 months; fuller cases are planned as Invisalign Go Plus, typically around 9 months. Adult bone remodels a little more slowly than a teenager’s, but the main factor is how far the teeth need to move, not age.
What is the shortest Invisalign treatment?
Invisalign Go Express, our shortest tier, takes typically around 3 months. A relapse case or a single small gap can be finished with 5–6 aligners over a few weeks of active movement, plus planning time at the start. Individual cases vary.
What is the 22-hour rule?
Aligners only move teeth while they are in. The plan assumes 20–22 hours a day of wear. Below that, teeth fall behind the aligners, the aligners stop fitting and treatment takes longer — often needing extra refinement aligners.
Why does Invisalign take longer than the dentist said?
Almost always one of three things: aligners worn under 20 hours a day, a tooth that stopped tracking and needed a refinement, or aligners changed early. Occasionally a tooth simply responds slowly. Refinements are a normal part of the process, not a failure.
How soon will I see results?
Most people notice a visible change in the front teeth within 4–8 weeks. The last few aligners make small, detailed movements you may not notice week to week.
How long do I wear retainers after Invisalign?
For life. Full-time for the first few months, then nights only. Teeth drift throughout adulthood whether or not you have had treatment; a retainer is what stops them. At Toothi all three tiers include removable and fixed retainers.
Want to know how long your own case would take? Book a free consultation with a free iTero 3D scan and you will leave with the likely number of aligners, the timeline and a fixed written price.
Call 020 3148 2444 or WhatsApp us · 1 Handel Parade, Edgware, HA8 6LD · Weekend appointments available.
