Monopsony

Monopsony is a key concept in economics — the mirror image of monopoly, but on the buying side of a market. It's especially important for understanding labour markets and wages, and it has become central to debates about employer power and the minimum wage. This guide explains what a monopsony is, how it affects wages and employment, why it matters, and where it shows up — in clear, plain language. It's relevant to anyone studying economics, labour markets or business strategy today.

What is a monopsony?

A monopsony is a market with a single dominant buyer — just as a monopoly has a single dominant seller. The buyer has enough market power to influence the price it pays, rather than simply accepting a price set by competition. While the textbook case is a sole buyer, in practice the term covers any situation where one (or a few) buyers have substantial power over a market. The most discussed example is the labour market, where the "buyers" are employers purchasing workers' labour, and a monopsonist employer has significant power over the wages it pays its staff.

How a monopsony affects wages and employment

The crucial feature of a labour monopsony is that the employer faces an upward-sloping labour supply curve: to attract more workers, it must offer a higher wage. But here's the catch — to hire one more worker, it typically has to raise the wage for all its workers, not just the new one. This means the marginal cost of hiring an extra worker exceeds the wage paid. A profit-maximising monopsonist hires up to the point where this marginal cost equals the value the worker adds — and because the marginal cost is above the wage, the result is that the monopsonist hires fewer workers and pays a lower wage than would occur in a competitive labour market.

A simple illustration

Imagine a large employer that dominates the job market in a small town. If it wants to expand its workforce, it can't just hire more people at the going rate — it has to raise wages to draw in additional workers, and (assuming it pays everyone the same) that raise applies across its whole payroll. Because each extra hire effectively costs more than that worker's own wage, the employer holds back on hiring and keeps wages lower than a competitive market would. Workers, with few alternative employers to turn to, have little bargaining power — so the wage settles below the value of what they produce.

Why monopsony matters: the minimum wage

Monopsony has a striking and counter-intuitive policy implication. In a competitive labour market, standard theory says a minimum wage set above the market rate reduces employment. But under monopsony, a well-set minimum wage can actually increase both wages and employment at the same time. The reason is that a minimum wage removes the monopsonist's incentive to hold down wages to limit its marginal cost — effectively flattening the supply curve it faces — so it's willing to hire more workers. This is a key argument used to explain why minimum-wage increases don't always cut jobs, and it's central to modern debates about employer power.

Where monopsony shows up

Monopsony power appears in many real settings. Classic examples include "company towns" historically dominated by a single large employer, but economists argue elements of monopsony are far more widespread — in local labour markets with few employers, in specialised professions where workers can't easily switch, and in some healthcare and education labour markets. It can also appear in product markets — for example a dominant supermarket chain as the main buyer for farmers' produce. Wherever buyers have outsized power and sellers have limited alternatives, monopsony dynamics can drive prices or wages below competitive levels.

Frequently asked questions

What is a monopsony?

A market with a single dominant buyer — the buying-side counterpart of a monopoly. The classic example is a labour market where one large employer has power over the wages it pays.

How does monopsony affect wages?

Because hiring more workers means raising wages for all, the marginal cost of labour exceeds the wage. A monopsonist therefore hires fewer workers and pays lower wages than a competitive market would.

Why can a minimum wage help under monopsony?

A well-set minimum wage removes the monopsonist's incentive to suppress wages to limit marginal cost, so it can raise both wages and employment — unlike in a competitive market.

Where does monopsony occur?

In company towns, local labour markets with few employers, specialised professions, some healthcare and education markets, and product markets with a single dominant buyer.

Master economics with Learnsignal

Concepts like monopsony deepen economic understanding. Learnsignal's tutor-led ACCA and CIMA courses build the foundations — with flexible, supported online study that fits around work.