How Much Does Invisalign Express Cost for Only Upper Teeth?

There is no cost benefit to upper arch only for Invisalign, express or full. Normally, Express will cost around $3-4000, but only applies if it can be done with 10 aligners or less.
Simpli5 is a good product, so if your case can be completed that way, I would not avoid it just because you are not familiar with it.

Nutella, thank you for your question.Invisalign Express is about $3,000-3,500, which can be paid in small monthly payments of less $99 with CareCredit and some down payment.

The cost of Invisalign varies by the number of retainers needed to achieve the desired result. Many of the answers I have read by some dental professionals unfortunately are incorrect. Simple tooth movement may be effective for only a single arch and often both arches do not need to be treated together. The process to design your smile starts with either a scan or impressions of your teeth. The Dentist will then prescribe a treatment based on the number of trays for teeth movement. Let's say Express 5. The software will show the maximum shift and best result with this number of retainers. Often we will need to move to a different system with more trays. Example Express 10. If we can achieve the result great, if not, the treatment may need to move to a full case. Always start conservative, assess then reevaluate to see if more aligners and time is required. Fail to Plan, Plan to fail.

Usually when you straighten the upper teeth, you have to also straighten the bottom so that the bite is right. Cost for one arch is the same for both arches in terms of Invisalign's material fee.

Remember one thing when shopping around, you'll need retainers at the end, make sure you have that calculated into the cost. Express works great for cases like yours. I dont have experience with the other companies.
Never do just one arch..there are always bite issues that need to be addressed when moving any teeth, upper or lower..its all the same price anyway, invisalign doesnt charge us less for just one arch and they frown upon doing it for patients.