Best Location to Stay for a Month in Paris

For four weeks, I like the following areas: the area around the Republique metro station, the area around, especially to the east of the Bastille metro station, the Batignolles neighborhood in the 17th arrondissement, the area around the Saint Georges metro station, or the area around the Censier-Daubenton and Place Monge metro stations. If you mean 2020, you should probably start looking now if you want a place that will be available for the entire month.

We have spent a month in the 20th near Pere Lachaise, several times in the 17th Batignolles nothing of tourist interest, several times in the 13th near Butte aux Cailles, in the 11th near Bastille, several times in Montmartre on Rue Caulaincourt and in the 14th just east of Montparnasse station and in the 7th. Loved em all except the 7th.

Our favorite area is the 17th the closer to Square Batignolles area the better but we enjoyed the others too. It is nice to be very central for a first short trip, but when you want to just 'be there' rather than touristing, a bit out of the center is best.

I am staying in Paris for just over 3 weeks in May 2020 also and am staying in an apartment in the 6th. I have stayed in the apartment before and know the area very well - close to all major areas plus Luxembourg Gardens is less than 5 minutes walk - would recommend the area
As others have said - I would book a.s.a.p. - I booked my apartment last June
I have used vrbo for past 4 times I have been in Paris (I normally go every 2 years)
https://www.vrbo.com

Thanks for the tips! I'm not familiar with the metro stops so the neighborhood listings are especially helpful. Are there any areas we should definitely avoid for safety concerns?

Dana, i’d recommend getting a good map of Paris that includes métro stops.
Good to understand the layout before you get there.
I’ve stayed in Paris many times for a month to 3 mos... my favorite areas are the same as a short trip... my favorites are the 4th arrondissement (the Marais and Ile St Louis - the little island next to the bigger island where Notre Dame is) and the 5th (Latin Quarter).
I like being as close to the river as possible, and as close to Notre Dame as possible. Notre Dame is the center of Paris, and the most central area.
I like being able to walk out onto the street and already be in the most beautiful, charming area of Paris (imo of course) and the most fun. And i like being able to walk to a lot of places, which you can do if you’re near the center.
Yes, you can take the métro anywhere, but it can involve a lot of walking and stairs underground - so no view. The métro can also be packed like sardines. You can take a bus but you can wait a fair amount of time for one (sometimes none come) and with traffic, it can take a while to get where you’re going.
My 3rd choice would be the 6th arrondissement (St Germain des Près) and in walking distance to the Luxembourg Gardens (which i love), as michael recommended.

I consider all of Paris (1st through the 20th) to be safe.

My daughter lived near Rue Bonaparte and Rue Jacob in Saint Germain and it was a fabulous location! You can definitely find something for your budget! I would look in that area and LeMarais if it was me!