Do I have to go through security at each airport when changing planes?

[busoulackova]

This is probably the stupidest question but I don't fly often and I've never had layovers before. 

I'm flying to Grand Rapids, MI and I have two plane changes. One change at Midway in Chicago and on the way back, I change planes at Baltimore/Washington D.C.

I've looked online but I've seen different responses. I know I'll need to go through security at my initial departing airport. Will I need to go through security again at Midway and at Baltimore?

Other information if needed: Changes are on the same ticket, bought at the same time so same reservation number. Layover at Midway is longer, over 4 hours while the layover at Baltimore is about an hour. No TSA pre-check or anything like that.

Thanks so much in advance, I always get so nervous when I fly since I'm not used to it! 

[DancingDavidE · Accepted solution]

---

@busoulackova wrote:

This is probably the stupidest question but I don't fly often and I've never had layovers before. 

I'm flying to Grand Rapids, MI and I have two plane changes. One change at Midway in Chicago and on the way back, I change planes at Baltimore/Washington D.C.

I've looked online but I've seen different responses. I know I'll need to go through security at my initial departing airport. Will I need to go through security again at Midway and at Baltimore?

Other information if needed: Changes are on the same ticket, bought at the same time so same reservation number. Layover at Midway is longer, over 4 hours while the layover at Baltimore is about an hour. No TSA pre-check or anything like that.

Thanks so much in advance, I always get so nervous when I fly since I'm not used to it! 

---

Domestic flying: no. Your bags will be checked through to the final destination and you can go straight to your next gate. You'll remain "airside" in the concourses at MDW and at BWI. (Four hours would be kind of tight to leave MDW and do anything fun and then get back, but possible. For BWI I recommend O'Brycki's inside the airport.)

You would only need to go through security if you booked one-way tickets from your origin to Midway and separate ticket from Midway to Grand Rapids.

The confusion online might be for international flights, in that case you likely would go through customs and be re-screened. There is a such thing as pre-clearance at Southwest destinations Aruba and Nassau where you would only be screened once at the origin, but there are several others with pre-clearance in Canada, Europe, and Middle East where you wouldn't be re-screened. Maybe that was the discussion you saw?

[CupCrusher40]

what if different terminal ?

[DancingDavidE]

---

@CupCrusher40 wrote:

what if different terminal ?

---

Both Midway and BWI can stay in the airside and get between concourses.

That is a good point - I once had to go through security in PHL because I flew Southwest from MDW to PHL, but then US Airways from PHL to GSO, and the concourse with the regional jets for US Airways wasn't connected to the Southwest concourse. There was a bus connection on airside, but it was faster to exit security and re-enter. I think this particular one is fixed now.

But in the vast majority of cases if you are staying on the same airline you won't have to leave security.

If you are changing airlines then yes you would, for one thing your checked luggage won't be transferred regardless of the gates. And then it would be possible at some airports that there are terminals or concourses that aren't able to be connected by walkways when tranferring airlines.

I believe OP was on Southwest the whole way though.