How to get from Charles de Gualle to Montparnasse

Paris is safe; this is not an issue. The biggest risk of public transport is pickpockets, so if you were to take public transport you would want to be sure your passport, phone, money, cards etc were well stowed and not where a skilled picker could get them.

The easiest is an official taxi from the ranks at CDG. They are well signed -- never go with anyone who offers a taxi 'need a taxi'. 'taxis over here'. etc. The official rank is well signed go there and get in line and the dispatcher will put you in a cab when you get to the head of the line. On our last two trips there has been virtually no wait -- maybe 3 people ahead of us. The longest we have waited in line is 15 or 20 minutes. Cabs will cost 65 to the left bank which includes Montparnasse. Have your address printed for the cabbie and some people like to go ahead and put 65 Euro on that paper. Make sure when you pull out the meter isn't running but 65 is on the meter.

The public transport route is RER B to Denfert Rochereau and then transfer to the 6 metro to Montparnasse then walk to your hotel. There will be stairs to haul the suitcase up and down. A taxi is money well spent in your situation.

Personal safety is not an issue. Pickpockets might be if you take mass transit and you might encounter a rip off artists at the airport. You can take a fixed rate taxi to the hotel. It will cost 65€ and is what I would do in your shoes. You should not accept a ride from anyone who approaches you. Follow the signs to the official taxi line. Official taxi stand locations are listed at https://www.parisaeroport.fr/en/passengers/access/paris-charles-de-gaulle/taxi under "Location of Taxi Ranks." If you want to take mass transit, it will cost about 12 euros. I suggest taking the RER B to Port Royal station and walking approximately 13 minutes to the hotel.

I’m a solo woman as well and I vote for a taxi too! What terminal are you arriving at? I just came in thru 2E (flying Delta) and there was enhanced signage for taxis. Look on the floor for blue circles that have footprints and say taxi. I was approached by several people asking if I wanted a taxi and my strategy is to ignore, look at the blue circle and go out the door to the line. I usually count on a few minutes in line to pull out my hotel address but there was literally no one in front of me so I just stepped to the side to get myself organized.

On the slip of paper (or I tape to a 3x5 card) also write 65€ out to the side.

I hope you are going a day or so ahead?

The Air France cars buses, now called RoissyBus or just Le Bus iirc, have a stop right at Gare Montparnasse,
and the stops at CDG are very easy to find, the drivers are pleasant, so are the fellow passengers, and you have a better view from the windows than in a taxi. And it costs about one third of what a taxi does.

If you do decide to go with a taxi, reserve one ahead over the website -- price is the same and you can pay ahead so no worries about cash or your card or phone not working right at the start.

https://www.about-paris.com/le-bus-cdg-line-4-to-gare-de-montparnasse.html

It looks like the walk from there to the Hotel Lenox is less than 10 minutes.
Just take a moment to get yourself oriented when you get off the coach bus.

Adding to say that the hotel website says 600 meters walk but the google maps directions say more like 750 meters. I'm saying that unless you have mobility concerns walking from the stop to the hotel is the best choice.

https://www.google.com/maps/dir/Rue+du+Commandant+René+Mouchotte,+Paris,+France/Hôtel+Lenox+Montparnasse,+Rue+Delambre,+Paris,+France/@48.8404562,2.3188531,16z/am=t/data=!4m14!4m13!1m5!1m1!1s0x47e670352befa54f:0x176910d87f87d0eb!2m2!1d2.3202118!2d48.8387972!1m5!1m1!1s0x47e671ceca7b7821:0x5fce9e575e759ec5!2m2!1d2.3277912!2d48.8415727!3e2?entry=ttu&g_ep=EgoyMDI0MTAwMi4xIKXMDSoASAFQAw%3D%3D

and and with the money and time you save you can drop your bag at the hotel and then go up the street to La Coupole and have an apero -- they have Saint Marcellin and they use Valrhona chocolate in the chocolat chaud.

https://www.lacoupole-paris.com/menus-carte/?utm_source=Google&utm_medium=GMB&utm_campaign=COU&y_source=1_MTE2NjUxODQtNzE1LWxvY2F0aW9uLndlYnNpdGU%3D#menu-32211

Just sayin'

Avi, Your post is several years incorrect. The bus to Montparnasse was stopped at least four years ago.
RoissyBus is completely different. That is the RATP bus that goes to the Opera. This information will send people down a rabbit hole.

Janet, Pam, and JHK gave you excellent information about the taxis.

And you do not reserve a cab ahead. G7 won't even do it from CDG unless you are booking a special ride like a van with car seats for babies or for a wheelchair. You go to the cab line and take the cab when it is your turn. And as noted that bus hasn't run in years.

Man I miss les Cars Air France.

As mentioned above the Air France bus. A/K/A Les Cars stopped running during the pandemic. It’s too bad because it was a great way to get to Gare Montparnasse without paying as much as a taxi or without having to change trains if taking the RER. The fact that there are still sites linking to it is really too bad.
As to taxis, as mentioned above, reserving one at CDG will not work with Taxi G7 unless you need a car seat or a special accommodation. A few days after you reserve but before the pick up, G7 will cancel the reservation because there are lots of taxis waiting at CDG for passengers.

And when you want to return to CDG book the taxi a couple of days in advance on the G7 English speaking line.

Don't forget about the 7€ charge for a taxi reserved ahead of time. It is well worth paying it IMO to be more sure of having a taxi when you need it. The charge is 4€ for immediate dispatch.

Just get in the official taxi line at CDG. Fixed rate. Easy as can be. Line is quick. We just did this in April.

If you need a taxi while in Paris any time except when departing CDG for your hotel, download the G7 Paris taxi app. Get a taxi wherever you are; very user friendly like the Uber app.

Solo, female traveler, also. I miss that bus! I’ve just been taking a taxi. After flying all night I’m not my sharpest…I don’t book ahead and have never had to wait long. I use an index card with the address and fare clearly written, which I give the driver. If you’d like to get familiar with the train station I’d recommend https://www.seat61.com. The Man in Seat 61 will provide photos and descriptions of the levels at Gare Montparnasse. I found it very helpful. He states platforms 1-9 are used by TGV trains which I’ve found generally true, however don’t assume this. 18-24 can also be and once I was on one that didn’t match either! No big deal, you’ll do fine. As others have suggested - take a moment and collect yourself. I feel if I look pulled together and not particularly friendly:) pickpockets are less likely to approach me. I highly recommend a smart watch to pay for EVERYTHING.

Thanks for the update, everyone -- so glad this came up before I leave :-)

this seems to be the updated summary info for getting from CDG to central Paris on public transit:

https://www.parisaeroport.fr/en/passengers/access/paris-charles-de-gaulle/public-transport

If I decide to use the RoissyBus to Opera then I will need to get on the 8 or the 9 to get close to my hotel,
so if the weather is glum, which is likely, I may opt for a taxi myself.

@ avirosemail, It may not make sense to take the Roissy Bus if you plan to take a taxi from rue Scribe to your ultimate destination, depending on the location. First, you will have to make your way to the Intercontinental Hotel to get a taxi. It's only about a 2-minute but the stand is not not right at the bus stop. If there are no taxis waiting at the Intercontinental which is unlikely but possible, the nearest taxi station is at Place d'Opera, another quick walk (maybe 2 or 3 minutes). But if you are tired and jetlagged, you may end up like a friend of mine did -- sort of wandering around the area with his luggage trying to find a taxi. Second, you will now be subject to regular taxi fares as opposed to the fixed rate from CDG and traffic happens.

I personally would take the RER B and the Metro, changing at Denfert Rochereau. But I much prefer trains to buses.

If you use the G7 app to summon a taxi on the street for immediate travel do you pay that 4 Euro fee?

If you use the G7 app to summon a taxi on the street for immediate travel do you pay that 4 Euro fee?

Yes. Only hailing a cab / using one waiting at a stand waives that fee.