You bet! Wash it and dry it in a salad spinner. If you do not have a salad spinner, swing it around in a towel. Chop it and seal it in a zip lock bag. Make sure the spinach is clean and dry and also express ALL the air out of the zip lock bag. You can also freeze creamed spinach :, in a saute pan saute 1/2 cup shallots, mild onions or leeks, 2 cloves garlic shopped in 2 TBS butter until tender. Add spinach just until it starts to soften, add 1/2 cup heavy cream, stir in 1/2 tsp black pepper, 1 tsp salt and 1/4 tsp nutmeg. Freeze in freezer bags. Thaw and top with parmesean or romano cheese and heat in oven in baking dish.
It is important that when freezing spinich that it is dry and the air is expressed to prevent freezer burn. Making creamed spinach prevents freezer burn and creates a ready to serve dish. Freezing just the spinach allows you to use it in veggie lazagna, spinach dip, spinach pizza etc :)