Following in the footsteps of Samsung, itself emulating Apple's strategy, OnePlus has today launched its own installment system for purchasing its products. That said, it's quite different from the others, since you can't switch devices after a set period of time. It's only available in the US right now, and you'll obviously have to use the OnePlus online store to buy what you want to pay for in monthly installments. The system can be chosen for any order that's over $99, but it's just an option - if you prefer to shell out the entire amount upon checkout, you can still do that too. To go the installment route, you need to select PayPal Credit as the payment option when completing your order. There's a calculator function that will then show up, telling you exactly how much you'll pay every month. For the OnePlus 2, going with the 18-month plan means you'll have to pay $22.60 every 30 days, while for the OnePlus X that's going to be $16.12 every month for one and a half years. Do note however that this isn't an interest-free installment arrangement. If you choose to pay monthly, by the end of those 18 months the OnePlus 2 will have cost you $406.80, which is $57.80 more than its $349 price. In the case of the OnePlus X, you'll end up paying $41.16...
Source: http://www.gsmarena.com/oneplus_unveils_its_own_installment_plan_for_the_us_market-news-17098.php