Fel cyrff annibynnol a chanddynt ddyletswydd statudol i weithio o fewn eu dyraniadau dros gyfnod o dair blynedd, disgwylia Llywodraeth Cymru i'r byrddau iechyd gymryd y camau angenrheidiol i fodloni eu dyletswyddau ariannol. Yn 2017-18, dywedodd pedwar bwrdd iechyd na fyddent yn gallu mantoli'r gyllideb a chynlluniasant ar gyfer diffyg yn eu halldro. I gynnal disgyblaeth ariannol y cyrff hyn, mae Llywodraeth Cymru wedi gosod cyfansymiau rheolaeth ariannol ar gyfer uchasfwm y diffyg yn 2017-18 fel a ganlyn:
As independent bodies that have a statutory duty to operate within their allocations over a three year period, Welsh Government expects the health boards to take the action needed to meet their financial duties. In 2017-18 four health boards indicated they would be unable to break-even and planned for a deficit outturn. To maintain financial discipline with these organisations, Welsh Government set maximum deficit financial control totals in 2017-18 as follows;Abertawe Bro Morgannwg £36.0 millionBetsi Cadwaladr £26.0 millionCardiff & Vale £30.9 millionHywel Dda £58.9 million