Answer: Fixed fee (based on linear inch of stump diameter) Explanation: Since some trees are easy to grind and others can be very hard, species is a factor, how large is the stump, how deep do you want it ground, how rocky is the ground, (I have done $100 in damage to my grinder on one stump), are there any hazards such as windows, wires, as water or gas lines. 
TORRISON TREE SERVICE 
Answer: Fixed fee (based on linear inch of stump diameter) Explanation: The answer is probably a combination of the stump diameter and the time it will take to grind it. The bigger the stump translates to more time spent on site grinding. 
Eager Beaver Stump Grinding 
Answer: Fixed fee (based on number of hours) Explanation: Most clients want the root system removed for new tree planting or new landscape 
Hernandez Tree Service 

ProMatcher 
Answer: Fixed fee (based on linear inch of stump diameter) Explanation: X $ per inch streight accross the stump at ground leval 
Desert Oasis Tree Service 
Answer: Fixed fee (based on linear inch of stump diameter) Explanation: $1 per square inch 
HIATTS TREE Experts 
Answer: Fixed fee (based on linear inch of stump diameter) Explanation: Yes 
Favored tree & fence services 

ProMatcher 
Answer: Fixed fee (based on linear inch of stump diameter) Explanation: Most companies charge by the inch at the widest point. 
Tri County Lawn & TreeService 
Answer: Hourly rate Explanation: Per hour and based on linear inch ot stump diameter 
Selena's Landscape, design & Tree Service, LLC 
Answer: Fixed fee (based on linear inch of stump diameter) Explanation: Many conditions affect stump removal costs. These include the diameter of the stump and root flair, presence of extensive roots, location of stump, presence of rocks etc. 
Oxford Outdoor Services LLC 

ProMatcher 
Answer: Fixed fee (based on linear inch of stump diameter) Explanation: Depends on the tree stump 
3G's Lawn care, landscaping & snow removal 
Answer: Fixed fee (based on linear inch of stump diameter) Explanation: All depends on diameter of the stump. 
Busy Bee Tree And Lawn 
Answer: Fixed fee (based on linear inch of stump diameter) Explanation: more stump more time 
ECT Contracting LLC 

ProMatcher 
Answer: Fixed fee (based on linear inch of stump diameter) Explanation: I price stump grinding by the diameter of the stump & the location of the stump & price accordingly. I also give a discount if there is more than one at the same location. 
mcintyres tree service 
Answer: Not sure Explanation: out of my field 
h.c.lawn& fence 
Answer: Fixed fee (based on linear inch of stump diameter) Explanation: Stump size 
Down To Dirt Stump Grinding 