Peel and rinse potatoes. Cut into even-sized cubes (1-inch x 1-inch approximately) and place them into a cold crockpot. Add cold water until potatoes are just covered and sprinkle with salt. Add lid and cook on high for 3 -4 hours or until fork-tender.
Drain potatoes and return to warm crockpot. Mash together with butter, cream cheese, milk and seasonings. Taste and adjust seasonings. Serve immediately.
If you'd like to keep these potatoes warm an hour or two before serving, switch to "keep warm" function and add 1-2 tablespoons of butter to the top of the mashed potatoes to keep them moist. If your crockpot runs a little hot, the bottoms of the mashed potatoes might scorch if left in too long, so just stir occasionally if you keep it warmer longer than two hours and keep an eye on them.