New salary sacrifice rules will reshape employer NI costs

In the lead-up to the 2029 reforms to salary sacrifice, there has been plenty of discussion about employee take-home pay. Less explored – and arguably more important for business leaders – is what these changes will mean for employer National Insurance contributions.

At Shawbrook, we have modelled the impact for two very different hypothetical 100-person employers: a specialist adult healthcare provider and a professional services firm. Their headcounts look the same on paper, but the way the new rules affect them could not be more different. And that difference is precisely why every organisation, regardless of sector, should be paying attention.

The first case, a healthcare provider, reflects what we often see in labour-intensive sectors: a workforce centred around lower- to mid-band salaries, typically between £25,000 and £35,000. Pension contributions in this range generally sit close to the incoming £2,000 NI-free allowance.

The second example – a professional services firm – shows the opposite dynamic. Here, higher salaries mean higher pension contributions, and most employees exceed the NI-free threshold from day one. When the new framework is applied, the outcomes diverge sharply. The healthcare provider faces an additional £12,050 in employer NI, with employees collectively paying £6,960 more. The professional services firm, by contrast, sees employer NI rise by £26,496, and employee NI by £13,598. The same number of employees, but the cost implications more than double. Workforce composition, not headcount, drives the result.

Despite these differences, the message for employers is remarkably consistent: National Insurance is going up, and materially so. Labour-heavy sectors such as care, hospitality and retail will feel the impact through sheer volume. Small increases per person add up quickly when payroll is broad and margins are tight. Higher-paid sectors will feel it through the scale of contribution, with pension payments overshooting the allowance far more easily. Different sectors, different pressures – but a shared financial reality.

For many healthcare providers, the timing is especially challenging. Rising wage expectations, acute staffing shortages and persistent cost pressures are already placing strain on operating models. An increase in NI simply compounds a familiar challenge: how to maintain quality of care while staying financially sustainable. Professional services firms face a different dilemma but an equally strategic one. Their task is to remain competitive in attracting talent, without allowing employer contributions to climb to a point that erodes margins or limits investment capacity. And across both examples, the impact flows straight through to the P&L, reducing retained earnings and weakening cashflow. These are the very metrics lenders, including ourselves, consider when assessing debt capacity.

In this environment, remuneration strategies will need rethinking. As salary sacrifice becomes less efficient, organisations may have to reassess pension contribution tiers, the mix of benefits on offer, and long-term salary progression pathways. It is not about cutting back, but about making sure reward structures remain competitive without inadvertently driving up NI exposure. Sensible financial planning – modelling future NI costs, stress-testing cashflow, and building additional headroom – will become increasingly important to avoid leaving investment plans exposed.

The reality is that the 2029 reforms will reshape the cost profile of workforces across the UK. Our modelling shows clearly that the scale of the impact varies, but the need to plan does not. Understanding how your workforce interacts with the new rules is only the first step. The real work lies in adapting reward strategies, managing cost pressures, and protecting financial resilience in a changing environment.