Start here: what does your own health system cover?
Before any conversation about private cost, the single most useful thing you can do is confirm what your own health system already provides, since for most women reading this page, reconstruction is available at no direct cost, or a substantially reduced one, through the same system managing your cancer care.
In the UK, breast reconstruction following NHS mastectomy is available on the NHS, either immediately or at a later date, and your specific options depend on your local service and your individual clinical situation, a conversation to have directly with your breast care team. In many other countries, reconstruction following mastectomy for cancer is either mandated by law to be covered by health insurers, or is a standard, funded part of cancer treatment pathways. This varies by country and by individual health system, which is exactly why confirming your specific entitlement, rather than assuming private international treatment is your only option, is the genuinely important first step.
Where funding is confirmed available, sequencing your reconstruction with your existing oncology team, who already know your cancer history, your radiotherapy plan and your overall treatment timeline, is generally the safer, more coordinated path than pursuing separate, privately arranged surgery abroad during active treatment.