Hyperkalaemia is one of the most frequent reasons for dose reduction or discontinuation of renin–angiotensin–aldosterone system inhibitors, and of mineralocorticoid receptor antagonists in particular, in patients with heart failure, chronic kidney disease and diabetes. Withdrawing prognosis-modifying therapy does reduce the risk of a further hyperkalaemic episode, but it increases the risk of disease progression, hospitalisation and death. The introduction of modern potassium binders – patiromer and sodium zirconium cyclosilicate (SZC) – reframes the problem: the therapeutic goal is no longer to lower serum potassium as such, but to create the conditions for delivering full guideline-directed therapy. SZC is distinguished by its rapid onset of action and its suitability for both correction and maintenance treatment. The REALIZE-K trial, conducted in patients with symptomatic heart failure with reduced ejection fraction and hyperkalaemia or a high risk of it, showed that continued SZC achieved an optimal response (normokalaemia, spironolactone ≥ 25 mg daily, no rescue therapy) in 71% of patients vs. 36% on placebo (OR 4.45, 95% CI: 2.89–6.86, p < 0.001). At the same time, numerically more worsening heart failure events occurred in the SZC arm (13 vs. 4) which, together with the sodium content of the formulation, warrants caution in patients prone to fluid retention. This article reviews the place of potassium binders in cardiological practice and proposes a practical treatment algorithm.