They are boxelder bugs and are more of a nuisance than harmful. The major objection to them is they congregate in clusters on the outside walls of your house, and then invade your home. They are also known to feed on developing apples, pears, grapes, peaches, plums and cherries when their populations are high.

This website from the Pacific Northwest Pest Management Handbook will provide more details. Boxelder (Acer negundo)-Western boxelder bug | Pacific Northwest Pest Management Handbooks (pnwhandbooks.org)

Being more of a nuisance, they can be vacuumed up in the interior of your home and on exterior walls. Seal cracks and crevices to keep them out.

If you are concerned about garden damage, the above website has a link to Chemical Control of Landscape Pests | Pacific Northwest Pest Management Handbooks (pnwhandbooks.org). You'll find chemical controls for boxelder bugs on p. 88, which gives a list of products available to the home gardener. As with all chemical controls read and follow directions carefully.