Ready-Mix vs Bagged ConcreteWhich Should You Use?
A complete comparison of ready-mix (truck-delivered) concrete and bagged concrete (Postcrete, Blue Circle) to help you choose the right option for your project size, budget, and timeline.
Quick Answer
Use bagged concrete for small projects under 1 cubic metre — fence posts, small pads, repairs, and anything you can mix by hand or with a portable mixer. Use ready-mix (truck delivery) for anything over 1 cubic metre — driveways, slabs, foundations, and large pours where consistent quality and speed matter. The cost per cubic metre is similar (£80–£120), but delivery fees and minimum orders make ready-mix impractical for small jobs.
What Is Ready-Mix Concrete?
Ready-mix concrete is batched at a central plant, mixed in a rotating drum truck, and delivered to your job site ready to pour. The concrete arrives fully mixed to the specified strength class (typically C25/30 or C30/37 for residential work), with the correct water-to-cement ratio already dialled in by the batch plant. You simply direct the chute or pump to where the concrete needs to go.
A standard ready-mix truck holds 6–8 cubic metres of concrete and can usually pour its entire load in 30–90 minutes. Most suppliers require a minimum order of 1 cubic metre, with part-load fees applied to orders under 4–6 cubic metres. The truck must have access within about 60 metres of the pour location, or you will need a concrete pump (£150–£300+ per hour) to reach further.
What Is Bagged Concrete?
Bagged concrete is a pre-blended dry mix of cement, sand, and aggregate sold in bags at builders' merchants and DIY stores. The most common brands are Blue Circle, Postcrete, and various own-brand mixes from Wickes, B&Q, and Screwfix. Bags come in 20 kg and 25 kg sizes. You add water, mix by hand or with a mixer, and pour it into your formwork. A 25 kg bag yields approximately 0.012 cubic metres of finished concrete, meaning you need about 83 bags to make one cubic metre.
Bagged concrete typically reaches C25/30 strength in 28 days, which is comparable to standard residential ready-mix. The convenience is that you buy exactly what you need from any builders' merchant, mix at your own pace, and require no heavy equipment access. The trade-off is that mixing is labour-intensive, and large volumes become impractical quickly — mixing 83 bags for a single cubic metre takes several hours of hard physical work.
Ready-Mix vs Bagged: Side-by-Side Comparison
How truck-delivered ready-mix and bagged concrete compare across the factors that matter most.
| Factor | Ready-Mix (Truck) | Bagged (Blue Circle, etc.) |
|---|---|---|
| Cost per Cubic Metre | £80–£120 per m³ (material only). Delivery fees of £30–£80+ may apply. | £100–£170 per m³ (about 80–85 bags at £4–£6 each for 25 kg bags). |
| Minimum Order | 1 m³ minimum. Part-load fees (£20–£50/m³) for orders under 4–6 m³. | No minimum. Buy as few or as many bags as you need. |
| Strength Class | Customisable: C20/25 to C40/50+. Standard residential is C25/30 to C30/37. | Standard C25/30. High-strength bags available at C30/37. |
| Convenience | Arrives ready to pour. No mixing required. Fast for large volumes. | Must be mixed on site. Labour-intensive for large quantities. |
| Mixing Time | Zero — arrives pre-mixed. Pour time depends on access and volume. | 3–5 minutes per bag by hand. 1–2 minutes per bag with a mixer. |
| Best For | Driveways, slabs >10 m², foundations, footings, large pours. | Fence posts, small pads, repairs, remote locations. |
| Shelf Life | Must be poured within 60–90 minutes of batching. No storage. | 6–12 months if kept dry and sealed. Buy ahead for weekend projects. |
| Quality Control | Plant-controlled mix design. Consistent batch-to-batch. Tested per BS EN 206. | Depends on your mixing technique and water ratio. More room for error. |
Cost Breakdown: Ready-Mix vs Bagged Concrete
The per-cubic-metre cost of concrete is surprisingly similar between the two options. The real cost difference comes from delivery fees, labour, and the scale of your project.
Bagged concrete: A 25 kg bag of Blue Circle or Postcrete costs £4–£6 at most builders' merchants (2024 pricing). Each 25 kg bag yields about 0.012 cubic metres. One cubic metre requires approximately 83 bags. At £5 per bag, that is about £415 per cubic metre in material alone. However, 20 kg bags (£3.50–£4.50) are more common for DIY projects and bring the cost to roughly £300–£380 per cubic metre. Factoring in the time to mix (easily 4–6 hours per cubic metre by hand), the total cost including your labour value is significantly higher than ready-mix for large pours.
Ready-mix concrete: The base price for standard C25/30 ready-mix ranges from £80 to £120 per cubic metre, depending on your region and the current cost of cement. Most suppliers add delivery fees (£30–£80 for a standard truck trip) and may charge part-load fees (£20–£50 per cubic metre) for orders under their minimum (typically 4–6 m³). A fuel surcharge of £15–£40 is also common. For a 3 m³ driveway pour, expect to pay £240–£360 in material plus £30–£100 in fees, totalling £270–£460.
Bottom line: For projects under half a cubic metre (about 40 bags), bagged concrete is almost always cheaper and more practical. For projects over 1 cubic metre, ready-mix saves you hours of labour and typically costs less per cubic metre once you factor in your time. The crossover point is usually around 0.5–1.0 cubic metres.
When to Choose Ready-Mix Concrete
Ready-mix concrete is the clear choice for larger projects where volume, speed, and consistency matter. Here are the situations where ordering a truck is the right call:
- Projects requiring more than 1 cubic metre — Mixing more than 83 bags by hand is exhausting, slow, and increases the risk of cold joints (where fresh concrete meets partially-set concrete). A truck delivers it all at once.
- Driveways, patios, and large slabs — A typical double driveway (6×6 m, 100mm thick) requires about 3.6 cubic metres. That would be 300+ bags. A ready-mix truck pours this in under an hour.
- Foundation footings and walls — Structural concrete for foundations should be poured continuously when possible. Ready-mix provides the volume and consistency that building control inspectors expect for structural work.
- Time-critical pours — If you have hired formwork, arranged a finishing crew, or have a narrow weather window, ready-mix eliminates the hours of mixing time that bagged concrete requires.
- Projects requiring specific strength classes or additives — Ready-mix plants can customise the mix with fibre reinforcement, accelerators (for cold weather), retarders (for hot weather), air entrainment (for freeze-thaw cycles), and custom strength classes.
- When you have good truck access — If the truck can back up within 60 metres of your pour location with a clear path, ready-mix is the most efficient choice. For tighter access, a concrete pump adds cost but still beats mixing hundreds of bags.
Rule of thumb: if your project needs more than 1 cubic metre, call a ready-mix supplier. The labour savings alone justify the delivery fee.
When to Choose Bagged Concrete
Bagged concrete excels for small, quick projects where ordering a truck would be overkill. Here are the best uses for bagged concrete:
- Fence posts and gate posts — Each post hole typically needs 1–3 bags (25 kg). You can set posts one at a time at your own pace, and fast-setting formulas like Postcrete let you pour the dry mix directly into the hole and add water on top.
- Small repair jobs — Patching a path section, filling a small hole, repairing a step, or topping off a deteriorated surface. These jobs might need only 2–10 bags.
- Projects under 0.5 cubic metres — Small pads for bin stores, hot tub bases, or small path sections. At 40 bags or fewer, mixing is manageable.
- Remote or hard-to-access locations — Garden projects behind fences, hillside retaining wall footings, or rural sites where a concrete truck cannot reach. Bags can be carried by hand to almost any location.
- Weekend DIY projects — If you want to work at your own pace without the pressure of a truck waiting (drivers typically allow 5–7 minutes per cubic metre before charging waiting fees), bags let you take your time.
- When you already have the bags — If you have leftover bags from a previous project or can get a good deal on a pallet, use what you have. Just verify the bags are still good (no lumps or hardened sections).
Rule of thumb: if your project needs fewer than 30 bags (about 0.35 cubic metres), bagged concrete is simpler, cheaper, and requires no scheduling.
Calculate Your Concrete Needs
Use our free concrete calculators to figure out exactly how many cubic metres or bags you need for your project: