Assessed contributions support organisational coherence, responsiveness and long-term strategic planning, as well as the ability to scale up results and address any unforeseen challenges in recipient countries. In the context of the UN Secretariat, ‘assessment’ refers to the amount the General Assembly determines is necessary to finance approved appropriations. Assessments are established through intergovernmental processes and apportioned among Member States based on the capacity to pay principle. Assessed contributions cover the organisation’s expenses, including the UN Secretariat regular budget, international tribunals, the Capital Master Plan and peace-keeping operations.

Table 1 shows that most, though not all, UN entities receive assessed contributions. This reflects the fact that many UN entities – particularly funds and programmes such as UNDP, the UN Population Fund (UNFPA), UNICEF and WFP – were established on the basis of governance arrangements and mandates reliant on voluntary financing. 

Table 3 provides a detailed overview of assessed contri-butions to the UN system by entity, highlighting absolute volumes for 2023 and 2024, as well as the share of assessed contributions within each entity’s 2024 revenue. These amounts are accompanied by sparklines illustrating the evolution of assessed funding since 2015 (or the year the entity began reporting to the CEB).

In 2024, total assessed contributions to the UN system amounted to US$ 13.8 billion, a decrease of US$ 50 million compared to 2023. Assessed contributions accounted for 93% of UN-DPO’s total revenue, with four other entities also receiving over 85% of their funding in this way: the Comprehensive Nuclear-Test-Ban Treaty Organization (CTBTO), the International Criminal Court (ICC), the International Residual Mechanism for Criminal Tribunals (IRMCT), and the World Trade Organization (WTO). As  entities tasked with upholding international legal and  normative frameworks, they benefit from stable, predict-able, impartial funding that ensures continuity of operations and safeguards their independence.

UN-DPO and the UN Secretariat together accounted for 70% of the UN system’s assessed contributions in 2024, which translates to US$ 6.3 billion and US$ 3.3 billion respectively (see Table 1 and Table 3). These numbers are below the approved appropriations and, thus, projected levels of revenue from assessed contributions. By December 2024, only 152 (out of 193) Member States had paid their contributions in full to the UN regular budget, equating to net assessments paid of US$ 2.4 billion.¹⁰ Outstanding assessed contributions from previous years represented 22.4% of the amount received in 2024, with one Member State responsible for 86% of the total outstanding amount.¹¹ UN-DPO has a separate budget, with a fiscal cycle ending on 30 June. For the 2024/25 financial period, US$ 421 million (or 8% of the budget) was not received.¹²

Assessed contributions are in theory mandatory, but enforce-ment mechanisms are weak, leaving UN entities and notably the UN Secretariat with limited means to sanction non-compliance. Although the UN Secretariat has faced liquidity constraints in the past, the situation has more recently deteriorated into an acute, recurrent crisis. Starting in 2022, there has been a continuous rise in unpaid assessments as of 30 September each year, growing from US$ 1.2 billion to US$ 1.5 billion in 2024 and US$ 1.9 billion in 2025. Payment delays and accumulating arrears have intensified cash shortfalls, requiring the UN Secretariat to borrow from the closed tribunals and the Working Capital Fund, and in 2024 withdraw resources from the Special Account, almost exhausting regular budget liquidity reserves.¹³

The 2020 shift from a biennial to an annual budget cycle has further constrained liquidity by limiting the use of resources received late in the year. For instance, the Secretariat received close to US$ 500 million in the final month of 2024. Delays in the receipt of assessed contributions restrict the effective use of resources within the same financial year, directly affecting programme delivery as ‘predictability in the timing and amount of collections is critical for managing the Organization’s cash outflows and to plan spending properly and safely without risk of payment default’.¹⁴ These liquidity pressures are compounded by a UN financial regulation that requires unspent funds be returned to Member States as credits against their future assessments, even when the approved budget has not been fully funded. In other words, the UN cannot simply keep any unspent money to help with future cash shortages.

Amid persistent late payments and a growing volume of arrears, the UN Secretary-General warned in a January 2026 letter to Member States of a deepening crisis ‘threatening programme delivery and risking financial collapse’. In the letter, he emphasised that ‘we cannot execute budgets with uncollected funds, nor return money we never received’, and called on Member States to revise the organisation’s financial regulations in order to limit the credits returned.¹⁵ The Fifth Committee decision of 30 June 2026 provided a significant breakthrough in addressing the UN Secretariat’s liquidity crisis, agreeing to end the practice of “returning” funds that were never collected from Member States. For a four-year trial period, unspent funds will only be returned to Member States when they are backed by cash, i.e. when the UN Secretariat does not fully spend the amount of payments received.¹⁶

Voluntary core contributions are unearmarked resources that UN entities can allocate flexibly in line with their strategic priorities and evolving needs. They may be provided in monetary or in-kind form and are particularly critical for entities that receive limited assessed contributions. The flexibility of voluntary core funding enables UN entities to respond to emerging crises, adapt programmes in rapidly changing contexts, support underfunded areas and ensure continuity in programme delivery. These resources also play a key role in financing core functions, strengthening institutional capacity and promoting system-wide coherence. As such, voluntary core funding underpins the effectiveness, independence and strategic alignment of the UN’s work. Given these contributions are not mandatory, however, they may be reduced, withheld or suspended at any time, posing challenges for predictability and planning.

In 2024, voluntary core contributions across the UN system amounted to US$ 5.3 billion, representing 8% of the  US$ 68.3 billion in total revenue (see Figure 2 on page 38 and Table 1 on page 40). Unitaid and the Joint United Nations Programme on HIV and AIDS (UNAIDS) stand out for the high share of voluntary core contributions in their overall funding, at 69% and 63% respectively.¹⁸ This reliance underscores the extent to which their roles within the global health architecture depend on sustained voluntary funding. It is also noteworthy that around half the International Fund for Agricultural Development (IFAD)’s 2024 revenue originated from voluntary core contributions.¹⁹ 

As in previous years, a small number of UN entities accounted for the lion’s share of voluntary core contributions in absolute terms, reflecting both their institutional mandates and donor priorities.²⁰ UNICEF received the highest volume of voluntary core funding at US$ 1.2 billion, including contributions from governments and unearmarked funds provided by UNICEF National Committees.²¹ WFP followed with US$ 609 million, while the UN Refugee Agency (UNHCR) reported US$ 586 million, the United Nations Relief and Works Agency for Palestine Refugees in the Near East (UNRWA) US$ 563 million, IFAD US$ 497 million, and UNDP US$ 493 million. Together, these six UN entities received close to three-quarters (74%) of the UN system’s voluntary core resources.

The ‘volatility’ in voluntary core contribution volume can partly  be attributed to the fact that when reporting financial data to the CEB in line with their audited financial statements, UN entities report revenue on an accrual basis, in accordance with the International Public Sector Accounting Standards (IPSAS). Thus, the full value of unconditional multi-year contribution arrangements must be reported upon signature. Here, it should be noted that some UN entities recognise revenue on a cash basis in management publications, such as the funding compendiums (for further details, see Box 3 in Chapter 3).

Earmarked funding is voluntary and provided at the discretion of contributors, with allocations guided by donor preferences, such as geographic focus, thematic priorities or expected outcomes. In 2024, as in the preceding four years, earmarked resources (US$ 41.4 billion) accounted for more than 60% of all resources received by the UN system, with project- or programme-specific contributions (US$ 30.6 billion) continuing to dominate. Like voluntary core funding, it is subject to change at the contributor’s discretion and may be reduced, delayed or interrupted at any time, creating challenges for predictability and planning. The rapid expansion of earmarked contributions up to 2022, followed by a sharp contraction in 2023 (see figures 1 and 2), is illustrative of both the modality’s inherent volatility and a broader shift in donor preferences towards more directed, “visible” forms of support. Earmarked funding is not inherently negative and has played an important role in expanding the UN system’s resource base. Member States value such funding for the control, visibility and results orientation it provides. 

Figure 5’s inner doughnut presents the distribution of 2024 UN system total revenue (US$ 68.3 billion) across the four financing instrument types. The outer doughnut further disaggregates the earmarked contributions (US$ 41.4 billion) by type, ranging from the more flexible modality of UN inter-agency pooled funds to (often tightly) earmarked project-/programme-specific contributions. The figure highlights a double concentration in the UN system’s financing structure. First, among the four financing mechanisms depicted in the inner circle, earmarked contributions account for more than 60%. Second, across the different types of earmarked resources, there is a strong concentration of funding directed towards specified projects or programmes.

The remaining revenue streams are grouped under ‘revenue from other activities’. This category encompasses income received by UN entities outside standard contributions and therefore not classified as such under their accounting policies. Since 2020, this revenue type has been reported across three sub-categories: 1) other revenue – specific to the  UN entity; 2) other revenue – other UN entities; and 3) other revenue – external to the UN. The first sub-category in cludes financial gains from investments, exchange rate fluctuations, and proceeds from the transfer of property, plants or equipment. The second and third sub-categories capture revenue earned from services provided on behalf of, respectively, other UN entities or external partners outside the UN system, such as governments, IFIs or the EU.²⁴

During the period 2015–2024, revenue from other activities more than doubled from US$ 3.5 billion to US$ 7.8 billion (see Figure 2). This growth can be divided into three distinct phases. Average annual revenue stood at US$ 3.9 billion from 2015 to 2018, increased to US$ 5.2 billion during 2019–2022, then expanded further to US$ 7.4 billion in 2023–2024. Based on the disaggregation introduced in 2020, the approximately US$ 2 billion increase seen in the latter period is largely down to a rise in revenue recorded under the ‘other revenue – specific to the UN entity’ sub-category. This reflects, among other things, favourable conditions for higher investment income and gains from exchange rate movements.

In 2024, total revenue from other activities amounted to US$ 7.8 billion, an increase of US$ 732 million on the US$ 7.0 billion recorded in 2023 (see figures 2 and 4). This equated to 11% of total UN system revenue for 2024, substantially higher than the 8% recorded for voluntary core. Entity specific revenue was responsible for US$ 4.3 billion of the total, with a further US$ 2.8 billion generated from services provided to partners outside the UN system and the remaining US$ 0.6 billion attributable to services provided to partners within the UN system.

A significant share of this revenue type is concentrated in the United Nations Office for Project Services (UNOPS), which accounted for 20% (US$ 1.6 billion) of the total in 2024. UNOPS operates on a full cost recovery basis, providing infrastructure, procurement and project management services to partners. It reports 100% of its revenue under ‘other activities’ and receives no core or earmarked funding. The World Intellectual Property Organization (WIPO), meanwhile, received 93% of its total income from fee-based services offered to users of global intellectual property systems.²⁵ The Pan American Health Organization (PAHO), for its part, obtained 74% of its revenue from other activities, notably by providing procurement services for vaccines and public health supplies.

Ongoing shifts in the international funding landscape have created revenue challenges for UN entities. Figure 6 presents the annual nominal revenue of select UN entities from 2015 to 2025. Collectively, the revenue of these ten entities accounted for 81% of UN annual revenue in the 2015–2024 period and represented 80% of the 2025 UN funding projection shown in Figure 1. Preliminary 2025 revenue data were subject to verification at the time of writing.

Revenue trends varied considerably across organisations, reflecting differences in mandates and funding models. Entities reliant on voluntary contributions, particularly those with large humanitarian portfolios, experienced a substantial expansion of revenues during 2020–2022, followed by a period of contraction as emergency funding levels eased and funding became more constrained.

Among the entities shown, WFP recorded the largest increase in revenue, rising from approximately US$ 5 billion in 2015 to a peak of over US$ 14 billion in 2022, before declining to US$ 6.9 billion in 2025, below its 2018 level. UNHCR followed a similar trajectory, with revenues increasing steadily from US$ 3.6 billion in 2015 to US$ 6 billion in 2022, before declining to US$ 3.6 billion in 2025, returning (in nominal terms) to its 2015 level.

UNICEF’s revenue grew significantly over the period, doubling in size from around US$ 5 billion in 2015 to more than US$ 10 billion in 2022, then falling for three consecutive years down to US$ 7.9 billion in 2025. UNDP’s revenue remained comparatively stable over the period in question, fluctuating between US$ 4.8 billion and US$ 6.6 billion.  

Of the ten UN entities depicted in Figure 6, UNDP is the only one to show a positive annual growth rate between 2024 and 2025, albeit a modest 3%.

Unlike the other UN entities mentioned above, UN-DPO is funded primarily through assessed contributions. Its  revenue levels exhibit a long-term downward trend, declining from US$ 8.8 billion in 2015 to US$ 6 billion in 2025, consistent with the downsizing and the closure of several peacekeeping missions.

The UN Secretariat, which is funded through a combination of assessed and voluntary contributions, saw its revenue increase gradually, and relatively steadily, from US$ 5.5 billion in 2015 to US$ 7.6 billion in 2024, before declining slightly to US$ 7.5 billion in 2025. Although year-to-year fluctuations were limited over the period, revenue has plateaued at around US$ 7.5 billion since 2023.

Overall, preliminary 2025 data indicate that the downward revenue adjustments observed since 2022 are continuing for the largest entities of the UN system. Several entities providing mainly humanitarian assistance have experienced substantial declines from recent peaks, reflective of a far more constrained international financing environment. The  numbers thus nonetheless provide an early indication of the financial pressure facing many UN entities in 2025, while the projections in Figure 1 indicate that the funding situation is expected to worsen further in the 2026–2027 period.