What is the shelf-life of your butter?

Our testing on shelf life of Chef Shamy butter began several years ago when I left a sealed garlic butter on my counter for 3 months and then sent it to the Food Sciences Division of Utah State University for testing. The butter tested good for 6 more months at that time. That is what gives rise to our 1 year shelf life (unopened) after manufacture. That said, here are the numbers and my suggestions:
 

1. Good up to 2 years frozen. (can be refrozen and re-refrigerated)

2. Good up to 1 year unopened in your fridge

3. Good up to 6 months after opening in your fridge if you use clean utensils
4. Good up to several weeks after opening on your counter. The time it will remain usable on your counter depends on
               a. ambient temperature
               b. cleanliness of utensils
               c. type of butter (garlic does the best as it contains the following bacterial inhibitors: Salt, Pepper, Garlic(which has been acidified with vinegar)
               d. Lemon dill Sautee butter should be refrigerated after each use as it tends to go rancid after a few days on your counter.
5. Our newest honey butter (Passion Fruit-Lilukoi) fits all of these parameters as Honey is a natural preservative

6. Our European Style Whipped Butter will keep refrigerated and frozen as above but should remain refrigerated between uses as it won’t last more than a few days on a kitchen counter

 
The long and short of it is, if you are going to use it up (like I do) it is easier to use at room temperature. If you are going to have it around for 6 months I would
definitely refrigerate between uses. That will give you a longer shelf life and a fresher taste. I have had Chef Shamy butter (honey and garlic) that stayed on my counter top
for weeks at a time. But the quality and flavor (like any butter) degrades over time.