Water is overflowing the gutters instead of draining down the spout.
Birds and small animals are nesting in your gutters.
Your gutters appear "mossy" or have plants growing inside.
You see stains, rust, or calcium streaks on your walls under the gutters.
Large puddles or standing water around the base of your home instead of near the downspouts.
It’s been more than a year since your last gutter cleaning.