Commissioner guide · Procurement
Spot purchase vs block contract vs DPS, explained.
The three ways a local authority buys supported accommodation for care leavers — what each one is, what it costs, and when to use it. Written for commissioners and social workers who need a clear answer, not a procurement portal.
By the Milestone Young People practice team · Reviewed: August 2026
There are three routes a local authority uses to commission supported accommodation for a care leaver: spot purchase (buy one placement at a time), a block contract (pay for an agreed number of beds up front), and a Dynamic Purchasing System (call off from an open, pre-qualified list). They differ on cost, flexibility, risk and speed — and most authorities use all three at once.
The plain-English version of this choice exists almost nowhere. It lives in council committee PDFs, freedom-of-information responses and procurement glossaries. This guide sets it out properly, so that a placing social worker, a commissioner and a provider all read the same page. Where a figure is time-sensitive we say so; the mechanics below are stable.
What is spot purchasing?
Spot purchasing is the direct commissioning of a single placement for one named young person, priced individually and bought only when the need arises. It needs no framework and no tender. A leaving-care team or a Personal Adviser identifies a provider, agrees a weekly rate for that young person, and places. It is the oldest and simplest route, and it remains the backbone of how urgent and unusual placements are made.
Its strength is speed and precision: a spot placement can be agreed in hours, and the price and support package are matched to exactly one person. Its weakness is cost and control. Because there is no volume commitment, the provider carries all the void risk and prices for it. When a placement is a same-day, out-of-area crisis — a breakdown at 9pm, a young person leaving custody with nowhere to go — the spot rate carries a large premium precisely because no planned local bed existed. Authorities that rely heavily on spot purchasing tend to be authorities that have run short of local capacity.
What is a block contract?
A block contract commits the authority to pay for an agreed number of beds or support hours over a fixed period, filled or not, in return for a lower unit price and guaranteed availability. The council reserves capacity — for example, a set of supported accommodation beds "for the exclusive use of the Council" — and pays for it as a standing cost rather than per occupied night.
Block trades flexibility for certainty. The authority gets a known price, reserved supply and a planning anchor; the provider gets predictable income and can invest in staffing and property with confidence. The risk sits with the commissioner: if occupancy is low, the authority pays for empty beds. Blocks are usually let through a tender or called off a DPS, are commonly evaluated on a quality-led basis (a 60% quality / 40% price split is typical for this cohort), and often sit behind an open DPS so that spot and block run side by side.
What is a Dynamic Purchasing System (DPS)?
A Dynamic Purchasing System is an open electronic list of pre-qualified providers that an authority calls off from, using spot or block call-offs, and which new providers can join at any point during its life. That open-ended admission is the defining feature — unlike a closed framework, a DPS does not shut its doors after an initial bidding round. A DPS can run for up to seven years, and a single one often covers looked-after children, care leavers, children in need, 16- and 17-year-olds at risk of homelessness and unaccompanied asylum-seeking young people together.
A DPS gives commissioners the best of both worlds: every provider on it has already been quality-checked (typically evidencing the four Supported Accommodation Quality Standards, registration where relevant, safeguarding, insurance and financial viability), so a call-off is faster and lower-risk than a fresh spot arrangement, while still allowing placement-by-placement flexibility. Many authorities buy children's and young people's placements through a DPS operated on an e-procurement platform such as Sproc.Net, which handles the referral, quotation and approval workflow between commissioner and provider.
The Procurement Act 2023 came into force on 24 February 2025 and replaces the term "Dynamic Purchasing System" with "dynamic market" for new arrangements in England. The mechanics are essentially the same — an open, pre-qualified provider list you can join at any time. DPSs set up under the earlier Public Contracts Regulations 2015 continue to run for their agreed duration, so both terms are in live use in 2026. [Confirm which regime your authority's current arrangement sits under.]
Spot vs block vs DPS: the comparison that matters
The three routes are not competitors — they are tools for different jobs. This table sets out how they trade off against each other on the dimensions a commissioner actually weighs.
| Dimension | Spot purchase | Block contract | DPS / dynamic market |
|---|---|---|---|
| What you buy | One placement, one young person | A reserved number of beds/hours | Access to a pre-qualified provider list; call off spot or block |
| Unit cost | Highest (premium on crisis/out-of-area) | Lowest per bed (volume discount) | Competitive; call-off priced per placement |
| Flexibility | Highest — buy only what you use | Lowest — committed whether filled or not | High — flex volume up and down |
| Financial risk | On the provider (void risk priced in) | On the authority (pays for empty beds) | Shared; authority pays for what it calls off |
| Speed to place | Fastest for a one-off; slow to assure quality each time | Instant once let, but slow to set up | Fast and quality-assured — providers pre-vetted |
| Quality assurance | Checked per placement (variable) | Checked at tender; ongoing contract management | Checked at admission and monitored on the list |
| Best for | Emergencies, complex one-offs, gaps | Predictable core demand, sufficiency planning | The standard "front door" for volume with control |
Which route should a commissioner use, and when?
Use a DPS or dynamic market as the default front door, a block contract for the predictable core of demand, and spot purchase for the genuine exceptions. In practice a well-run authority layers all three:
- DPS / dynamic market for the bulk of planned placements — it delivers pre-checked quality at call-off speed and lets a new local provider come onto supply without waiting for a tender round.
- Block contract where demand is steady and forecastable enough to justify reserving beds — this is the route that builds sufficiency (see our guide to the sufficiency and "suitable accommodation" duty) and brings the unit price down.
- Spot purchase for emergencies, one-off complex needs the block and DPS cannot match, and to cover gaps while capacity is being built. The aim is to shrink reliance on high-cost crisis spot placements by growing planned local supply — the more you spot-buy out of area, the more the crisis premium costs.
The direction of travel in most authorities is to move volume from expensive out-of-area spot placements onto local DPS and block arrangements, both to control cost and to keep young people closer to their support networks, education and Personal Adviser.
The Light Touch Regime — why care placements are procured differently
Supported accommodation is a "social and other specific service", so it is bought under the Light Touch Regime — a lighter, more flexible set of procurement rules than apply to ordinary goods and services. Under the Light Touch Regime an authority has more freedom over how it runs the process, provided it is transparent and treats providers equally, and the financial threshold at which the full rules bite is substantially higher than for other contracts. This is why DPS admission for care placements can be relatively quick and why frameworks in this space are often described as "Light Touch". The regime continued, in modified form, under the Procurement Act 2023. [The Light Touch threshold is reviewed periodically — confirm the current figure before relying on it for a specific procurement.]
Where the money goes: rent and support are two separate lines
Whichever purchasing route is used, it buys the support — the rent is met separately by Housing Benefit. This is the single most important thing to get right in a supported accommodation placement, and the one most often muddled. A compliant placement has two funding streams that must never be blended:
| Funding line | Pays for | Who pays | Bought via |
|---|---|---|---|
| Rent / accommodation charge | The accommodation itself | Housing Benefit (care leavers in supported accommodation claim HB for rent, and Universal Credit for living costs) | Housing Benefit claim — not the commissioning route |
| Support charge | Keywork, independent-living skills, safeguarding, EET and health support | The commissioner (leaving-care / commissioning budget) | Spot, block or DPS call-off |
When a commissioner agrees a "weekly rate" on a spot, block or DPS call-off, that rate is the support line. The rent sits with Housing Benefit. Keeping them apart matters for audit, for Housing Benefit compliance and for value: each is scrutinised by different people, and each dislikes finding the other smuggled into its column. For care leavers under 25 there is also a Housing Benefit lever worth knowing — the Shared Accommodation Rate exemption — which lifts the rent a self-contained placement can attract; we cover it in the young-people guides.
We are built to be commissioned every way a young person needs. We are readying for the Dynamic Purchasing System route, we quote transparent needs-banded rates for spot placements including emergencies, and we hold capacity that can support a block arrangement where an authority wants reserved local beds. Rent and support are always quoted as two clear lines.
Frequently asked questions
What is spot purchase in supported accommodation?
Buying a single placement for one named young person at an individually agreed weekly rate, called off only when the need arises. No framework or tender is required, which makes it fast, but it is the least price-controlled route — spot rates carry a premium, especially for same-day or out-of-area crisis placements.
What is the difference between a block contract and spot purchase?
A block contract commits the authority to pay for an agreed number of beds or hours over a period, filled or not, at a lower unit price with guaranteed availability. Spot purchase buys one placement at a time at a negotiated rate with no volume commitment. Block trades flexibility for price and supply certainty; spot trades price for flexibility.
Can you spot-purchase from a provider on a DPS?
Yes. A DPS supports both spot and block call-offs, so an authority can place a single young person with a DPS provider at a call-off rate while the same DPS also underpins block arrangements. That is much of the appeal — pre-qualified quality with placement-by-placement flexibility.
Which route is cheapest?
Block contracts are usually cheapest per placement because volume is guaranteed. Spot purchase is dearest, and dearest of all as a crisis, out-of-area placement. The trade-off is that a block contract carries the risk of paying for empty beds, so "cheapest per bed" is not always "cheapest overall" if occupancy is low.
Do rent and support come out of the same budget?
No. Housing Benefit meets the rent; the commissioner pays for the support from the leaving-care or commissioning budget. They are two separate lines and must not be blended in a single charge — whichever purchasing route buys the support, Housing Benefit still meets the rent.
Sources and further reading. Public Contracts Regulations 2015 and the Procurement Act 2023 (in force 24 February 2025), legislation.gov.uk; DfE statutory guidance on sufficiency of accommodation for looked-after children; the Supported Accommodation (England) Regulations 2023 and the four Quality Standards (see our Regulations 2023 summary). Figures marked time-sensitive should be confirmed against the current source before use.
Placing, or planning capacity?
Whether you need a spot placement this week, are shaping a block arrangement, or want us on your Dynamic Purchasing System, talk to us about placements and how we price them.