This looks like a male wolf spider. The spider is not poisonous and beneficial. It is a good predator and feeds on many pest insects. Let it go outdoors.
Thanks for your quick response! My husband is a biologist and was looking online himself for a possible identification. He thought it was a dark fishing spider based on the Ws on the back and the coloration. I have attached some better pictures here. The ones from before are quite fuzzy. Can you let me know the differences between the wolf spider and the fishing spider please? Many thanks!
Fishing spiders can be easily confused for wolf spiders, so that is a possibility as well. Spider families are typically differentiated by eye arrangement, so without a clear image of this, it is difficult to tell, and there are multiple species that look very much alike. You can peruse the listings below for each on Maryland Biodiversity Project's pages, as they have collections of photos for each species. To make it simpler to view, you can click on the photo icon near the top of each main list page to see an array of thumbnail pictures so you don't have to open and look through each species gallery.
wolf spiders, family Lycosidae: https://www.marylandbiodiversity.com/viewChecklist.php?family=Lycosidae
fishing spiders (a.k.a. nursery web spiders), family Pisauridae: https://www.marylandbiodiversity.com/viewChecklist.php?family=Pisauridae
grass spiders (also called funnel-web weavers), family Agelenidae: https://www.marylandbiodiversity.com/viewChecklist.php?family=Agelenidae
(it may not be this, but they too are vaguely similar and can end up indoors)
There are a few guides online to eye arrangement in spiders; here is one that includes some of these three families: https://bugguide.net/node/view/84423