So this is quite complex....<p>You need:<p>1. Merchant Account
2. Payment service provider
3. Billing software (your own or someone else)<p>Like you, we are UK based business, who wants to charge in dollars. Wanting the flexibility of having our own merchant account, the better rates that should give, and the portability of your customers (and their card details) I first of all spoke to the banks. But some won't deal with startups without 2 years trading history (HSBC and LTSB for example). Some don't charge in anything other than GBP yet (Clydesdale). And some, such as Barclays, although they will charge in both USD and GBP want to charge exorbitant rates for USD transactions. (2 or 3 times typical GBP rates).<p>You also need to make sure your merchant bank support recurring transactions; not all do!<p>Setting up a merchant account can take weeks and a lot of paperwork and hassle. In the end, for competitive multi currency rates and simplicity we opened an account with PayPal Website Payments Pro. This took around 48 hours!<p>It also killed the requirement for a payment gateway, which reduces the cost and complexity again. The downside with PayPal is, I believe, that if we wanted to move in the future, our customers would have to re-key their payment details with our new provider.<p>Regardless of whether you are with PayPal, or a bank+PSP the next step is the recurring billing.<p>Putting together these three separate providers together can be a bit of a nightmare. Although most banks support most payment gateways, most recurring billing providers only support a minimal number of gateways.<p>If you are in the UK and want to use Chargify you have no choice but to use DPS Payment Express (an Australian company) and they in turn only work with HSBC or Barclays.<p>Recurly support (for the UK) Cybersource, SagePay and PayPal Website Payments Pro.<p>Spreedly supports more, but for some reason that I now can't remember I counted them out.<p>The thing about billing is that it quickly becomes pretty complex and the smaller providers have all got limitations which could, depending on your business model, cause problems. You can imagine that with however many customers they all have, there will be a lot of requests to them along the lines of "can you just add this... that would be great". It must be hard for these guys to keep up with such requests.<p>When you look at the recurring billing providers you may also need to look at whether they support multi currencies, and VAT.<p>That's all I can think of for now. Good luck!