That depends on a number of factors. How long ago was this wood chipped? Was this wood green and still growing when chipped? How much moisture is in that pile of wood chips? Was any Nitrogen added to this mix? How big is this pile of wood chips?
Sometimes the 6 to 8 inch wood chip mulches I plunk down will get digested in one year while other times, and maybe places, those wood chips will last several years.

My truck load of tree trimming chips from living trees are almost cooked down to nothing in less than a year ... where used in pathways and as mulch in planting beds. [& earthworms love this material]

But in the heaps where I piled the material I didn't find immediate use for, the chips are dry and musty below the first 2 inches .. and this is spite of an extra wet year.

Also, the chipped material that I added to a compost pile along with horse manure, kitchen waste, and other garden waste -- has cooked down into some pretty nice stuff ... though the larger chips are still not composted, they will go back into the new pile and next year will disappear.

Hope this helps with your question. I'll be ready for another truck load this summer.FREE is the operative word, but water rentention is HUGE here in SoCal, so I mulch, mulch, mulch and these trimming/chips have proven to be primo.

A huge chip pile in a parking lot where I worked was still a quite woody after two years, but mixed with a lot of "dirt" from worm castings etc. For my own truckload sized piles I add inexpensive high urea yard fertilizer and have got usable young compost [for improving bad clay soil] over winter [late Fall chipped, used in Spring], composted under snow. But a full year is better for mixing into good garden soil. It needs to be turned and wetted down every month or so, which is pretty easy with a pitch fork. Best to add more nitrogen at those times.

Over the years....50 plus now....I have had wood mulch and chiped wood in piles every way you might be able to think of. I have experienced all of the above many times over. There is no magic.....just go ahead knowing that some years or ways you use it will present you with different time periods to arrive at finnished compost.

I like them best as permanent mulch in my foundation and flower beds all maintained with two to four inches in place. I've been at my present location for thirty five years. Some of my beds have been that long under permanent mulch. My major beds were created over a ten to fifteen year period.

We lost a giant old Spruce a few weeks ago and I had the tree removers leave the chips in a pile in my yard. I've slowly been using it around the garden, but I can tell you that the green areas of mostly needles and twigs has been composting super-fast, whereas the areas that were mostly actual wood chips aren't composting at all. We have had record amounts of rainfall over the past month until the last few days. I didn't add anything to the pile, but I did add some yummy (for microbes) fungus covered needles to my compost bin a few days ago; the rest has been going towards amending my clay soil and a good layer on top of a raised bed that should be ready for next year.

Boy does this forum make me jealous! Everybody gets all this free stuff - free wood chips, free poop. Not here in NY - you must pay for EVERYTHING! I was actually surprised that the tree removers didn't charge me for my own wood chips (they probably would have if it was cedar). When they removed the stump (using a giant front-loader that totally cracked and smashed a big gully into my driveway) I asked about buying topsoil to fill in the hole - $50 a cubic yard. I'm now filling it with clay that I dug out of my backyard to create a drainage well mixed with leaves and wood chips. I hope my wormies love me :) We actually paid the tree removers $100 to cut up the top 40 feet of an old Sassafras that fell in the backyard (because we had no power and our chainsaw is electric and the trunk was caught in the fence and on top of our birch tree); we still have to cut it smaller and split it, but at least we got some firewood out of it. Removing the remaining 30-40 feet of tree that is still in the ground is going to cost a fortune because it is too close to my neighbor's garage (and now I want to wait until next year because a nice raccoon has already moved in). Most people around here pay to have all this great stuff removed - just watching all the giant tree trunks drive down my road in trucks made me sick; I kept thinking half pine (wood chips) half maple and oak - that's at least $2,000 worth of firewood that people PAID to have taken off their property just so the tree removers can charge those of us with wood stoves $200 a cord (some places charge up to $500 a cord around here). We actually had our Spruce removed for $350 as opposed to other removers who averaged $500 (for an uprooted tree not on a house) because we get our firewood from them.

Think you all and yes I should have used common sense and realized, that certain factors do apply. I have a few acres I'm not using and found a tree chipper needing a place to dump. I thought I could use some for mulch and thought being organic material it would some day be compost. I just did not know how long to expect it to take.