You can now transfer miles for free between the two programs, so you get to monitor twice as many promotions.
And you can link them so you get rewards on both… see thepointsguy.com. The biggest one is to get a free Continental card and then you get 25k miles for free 😉 And Continental has Hawaiian as a partner, so you can use your United miles by tranferring to Continental for Hawaiian airlines travel…
 

  1. Transfer redeemable miles between your OnePass and Mileage Plus accounts. Give it a spin at united.com/transfermymiles or continental.com/transfermymiles (both take you to the same place).
  2. Match Elite status and combine Elite earnings for your OnePass and Mileage Plus accounts. For those of you who have Elite Qualification miles and segments/points in both OnePass and Mileage Plus, you can now combine these earnings to earn Elite status, Regional Upgrades and Systemwide Upgrades. Go to united.com/combinemyactivity or continental.com/combinemyactivity for all the details. “

And here are the advantages
1) Combining your Continental and United miles allows you to redeem for better awards. If you have 12,000 United and 13,000 Continental, you can combine to have enough miles to book a domestic round-trip coach award.
2) United allows one way awards (even on Star Alliance partners), while Continental does not. If you need to book a one way award and you have Continental miles, simply transfer them to your United account.
3) Continental is a transfer partner of American Express Membership Rewards, so until September of this year, you can transfer Amex -> Continental -> United, allowing you to book one way awards, even on Star Alliance partners
4) Emirates is a partner of United and they allow first class awards for 210,000 miles, business class for 150,000 and coach for 90,000. 
5) United blocks some partner awards (Starnet Blocking), while Continental does not. While United has gotten better about this recently, award availability and routing rules are generally more lenient with Continental.
6) Continental.com allows more Star Alliance partners to be booked online, thus saving you time and money from having to call United (who may charge $25 per ticket for booking with a phone rep). Continental’s online engine is a better booking engine with more Star Alliance partners. While it doesn’t show international first class (only economy and domestic first/ international business), it does load a lot of Star Alliance partners like Lufthansa, ANA, Thai, TAP, US Airways, United, Air Canada, bmi, Spanair, SAS, Brussels Air, EgyptAir, and Aegean (let me know if I’m missing any).
7) Take advantage of double the amount of partners and promotions. For the time being, Continental and United have different credit cards, though they are both issued by Chase, so you should wait at least 6 months after applying for the first. Their current offers are pretty generous- 50,000 miles and no fee for the Continental card and 30,000 miles and no fee for the United card. Add in a 50,000 point sign-up bonus for the American Express Platinum card and you’ve got more than enough miles for that business class trip on Emirates (or first class on Star Alliance to Europe) – all without stepping on a plane and for only $450 in fees (for the Platinum card).
8 ) Take advantage of other airline partners. United’s are Aer Lingus, Emirates, Hawaiian, Island Air, JetQatarand Taca. Continental’s non-Star Alliance partners are: CopaVirgin Atlantic, Emirates, EvaAmtrak, Cape Air, Hawaiian, Aeromar and Island Air.
9) United members can take advantage of Mileathon.

I’m Rich & Co.

Welcome to Tongfamily, our cozy corner of the internet dedicated to all things technology and interesting. Here, we invite you to join us on a journey of tips, tricks, and traps. Let’s get geeky!

Let’s connect