Prep all ingredients. Put slow cooker on low setting.
Add chicken broth, onion, leek, celery, garlic, butter, salt, and pepper to the slow cooker. Cover and cook on low for 1 hour.
Once vegetables have softened, add clams, clam juice, cooked bacon, cream cheese, and heavy cream.
Stir together until cream cheese is softened and well incorporated. Add thyme and stir again. Cover and cook for 6-8 hours on low.
Optionally: Turn slow cooker to high and leave the lid off for 30 minutes if you want to reduce the chowder to make it thicker.
Serve hot and enjoy!