What is the shortest amount of time you'd feel comfortable with transitioning from an airplane to an SJ train at T-Centralen?

In the past, I have caught a train at around noon. This year, it appears that the only options are 9:07am and 12:55pm.

My UA EWR-ARN flight lands at 7:35am. I will be sitting in the second row of economy, so only about 27-30 people in front of me. I will probably have two checked bags (maybe just one) with *A priority tags--which I've seen don't really help. I'm familiar with getting to Arlanda Express as well as nagivating Stockholm Centralstation.

Is 90 minutes too close for comfort? There is a train that leaves at 9:25am from Stockholm Centralstation, but I would have to change in Hallberg. Could I buy a ticket for the 9:07am train, and then take the 9:25am train in case I miss it? What I find strange is that the 9:25am train would then connect with the 9:07am train.

I could take a bus (Bus4You) from ARN at 9:15am, but it seems like their baggage policy could cause an issue.

1.33 hours to 2.5 hours, but I guess it may vary (a good deal less or more) based on the costs arising from failing to connect from ARN plane to T-centralen-departing train. If there is a baggage handling irregularity for checked in luggage that you discover after the delivery of all bags from the plane, it's possible to lose up to 75 minutes at ARN just dealing with that.

I doubt that your train is leaving from T-Centralen. T-Centralen is a subway station (Stockholms tunnelbana) with no long-distance trains. There is no station named Hallberg on the Tunnelbana, so I presume that you are going through Hallsberg.

Your station is called Stockholms Centralstation (Stockholm C) which indeed is adjacent to T-Centralen. With two checked bags, this sounds a bit risky to me, even with a prebought Arlanda Express ticket

According to the Bus4You-homepage extra luggage can be prebooked. An extra piece of luggage (max 25 kg) on top of the one piece plus hand luggage included ARN-Karlstad costs SEK49, so I'd probably go for the bus.

pseudoswede has been to the Stockholm Centralstation a fair amount at least -- it seems to be on average at least an annual thing for him.

For some of us -- including some resident in Stockholm -- we refer to the area as T-Centralen just because that's the name of the T-bana stop we use when using Centralstation in conjunction with the T-bana even as T-Centralen is indeed formally not the same thing as Stockholm C.

His train is indeed not going to be a T-bana train, so it would be the Stockholm C tracks that he ends up using. But to go from Arlanda Express or the buses to use the tracks -- most of those involve heading sort of toward a T-bana-user level before going back up to get on the train he is likely to be using.

Postings and answers to them are not only read by the OPs, but also others. Even though the OP probably wil have to go to a subterranean level of Stockholm C, to reach the track for his long distance train, to call this T-Centralen is quite misleading as the actual station T-Centralen (i.e. the tracks and platforms) is located some distance away, closer to Sergels Torg.

I have not heard the whole area referred to as "T-Centralen", but rather as "Centralen", which refers both to the railway station (which was there first, and having a square called Centralplan in front of it) and the subway station.

When I'm using T-Centralen to use the T-bana platforms or Stockholm C platforms in relation to journeys to/from ARN, it's much closer for me to use Stockholm C to access trains, T-bana trains or otherwise, than to use Sergelstorg to access trains.

When speaking of T-Centralen, Central Station and Centralen to refer to doing transport hub interchanges, referring to the same as Sergels torg has a quite distinctive connotation than co-mingling the former two or three. Calling it T-Centralen, Central Station, Stockholm C or Centralen ought not to be that confusing to people. Calling it Sergelstorg is another matter.

ksu has a point. I just find writing T-Centralen easier. I will edit my OP to the proper name.

I have lost track, but this will probably be my 18th time transiting through Stockholm.

It's probably what I'll plan to do. Even if I miss the 9:15am bus, there is another one two hours later. As much as I like walking around Gamla Stan during my layover, being able to relax and avoid Centralen is worth the extra kronor.

Update: I did book the 9.15 bus about a week ahead of departure. I even splurged and spent the extra 9 SEK for a reserved seat.

My UA flight arrived almost an hour early, but we had to wait on the tarmac for 30 minutes due to no gates available. I quickly made my way to immigrations, and my one checked bag (with priority tag) was amongst the first off the plane. I was in the arrivals hall around 7.45.

I had a fika, recharged my phone, then boarded the bus. Never questioned how much my bag weighed. Four hours later, I was back in the arms of my loved ones.

We'll probably take Bus4You for our return trip. It's nice to basically get off the bus and go directly to the Clarion Arlanda, especially since we have to wake up at 5am. The price differential between the bus and train (+ Arlanda Express) makes it practically a wash.