The new deal from T-Mobile requires no down payment, and 24 monthly installments of $16.50. Math might not have been our best subject, but we can tell you that it works out to a price of $396. While that is still $47 more expensive than the price of the 16GB Nexus 5 purchased directly from Google using the Google Play Store, it does allow you to pay for the phone over 2 years instead of paying all at once.
If you're flush with cash, you might want to head over to the Google Play Store where the 16GB Nexus 5 is priced at $349 and the 32GB model is $399.
T-Mobile has cut $54 off the price of a 16GB Nexus 5
source: T-Mobile via AndroidAuthority