Meal prep lives or dies on the quality of your containers. The wrong ones leak in your bag, warp in the microwave, crack after a few washes, or take up so much cupboard space that you give up before the habit sticks. The right ones become invisible — they just work, every time, without you having to think about it.
This guide covers what to look for in a reusable food container, which sizes suit which uses, and where to buy BPA-free, microwave-safe, leak-proof food containers with lids online in the UK without overpaying.
What to Look for in a Reusable Food Container
BPA-Free Plastic: Why It Matters
BPA (bisphenol A) is a chemical used in some plastics that has been linked to health concerns, particularly when containers are heated. Reputable food containers are now manufactured BPA-free as standard — but it's worth confirming before you buy, particularly for containers you'll be using in the microwave regularly. All the plastic food containers stocked at Reign Goods are BPA-free.
Microwave-Safe Food Containers
Not all plastic is microwave-safe. Containers that aren't rated for microwave use can warp, leach chemicals into food, or crack under heat. Microwave-safe containers are made from polypropylene (PP) plastic, which tolerates the heat of a microwave without degrading. Look for the microwave-safe symbol on the base of the container — a box with wavy lines — or confirm it in the product description before buying.
For meal prep specifically, microwave-safe containers are essential. The whole point of prepping food in advance is being able to reheat it quickly and easily — a container that can't go in the microwave defeats the purpose.
Leak-Proof Lids
A container with a lid that seals properly is non-negotiable for anything you're carrying in a bag. Loose-fitting lids are fine for fridge storage but will cause problems the moment you put them in a lunch bag. Look for containers with locking clip lids or snap-fit lids that create a proper seal. For liquid-heavy meals — soups, stews, sauced dishes — a fully airtight seal is worth prioritising.
Freezer-Safe and Dishwasher-Safe
Freezer-safe containers allow you to batch cook and freeze portions in the same container you'll reheat from — no decanting, no extra washing up. Dishwasher-safe containers save significant time over a week of meal prep. Both are standard features on quality plastic food containers; confirm both before buying if you plan to use them for batch cooking.
Which Size Food Container Do You Need?
Size is the detail most people get wrong on their first meal prep container purchase. Too small and you're cramming food in; too large and the container is half-empty and takes up unnecessary space. Here's a practical guide:
| Container Size | Best For |
|---|---|
| 500ml | Snacks, side dishes, fruit, small portions, children's lunchboxes |
| 650ml | Standard adult lunch portions — rice and curry, pasta, salads |
| 1000ml (1 litre) | Large meal portions, batch cooking single servings, soups |
| 680ml round (24oz) | Gym meal prep, protein-heavy meals, rice and protein combos |
| 909ml round (32oz) | Larger appetite portions, bulkier meals, family-sized servings |
| 1360ml round (48oz) | Family batch portions, large salads, multi-component meals |
For most adults doing standard weekday meal prep — lunch and dinner portions — a mix of 650ml and 1000ml containers covers the majority of meals. If you're prepping for the gym or cooking high-volume protein meals, the round 32oz containers are a better fit.
Rectangular vs Round Food Containers
Rectangular containers stack more efficiently in the fridge and fit more neatly into standard lunch bags — they're the better choice for everyday meal prep and fridge storage. Round containers are better suited to certain types of food (rice dishes, curries, soups) and tend to be easier to eat from directly. Both are useful; most households that meal prep regularly end up with a mix of both.
At Reign Goods, we stock both formats:
- Rectangular with lids: 500ml, 650ml, and 1000ml — BPA-free, microwave, freezer and dishwasher safe, leak-proof lids
- Round with lids: 24oz / 680ml, 32oz / 909ml, and 48oz / 1360ml — same spec, better for bulkier meals and gym prep
Sauce Pots and Small Containers with Lids
Meal prep isn't just main portions — dressings, dips, sauces, and snacks all need their own containers. Small sauce pots with lids are the detail that makes a packed lunch actually work: your salad dressing stays separate until you're ready to eat, your dip doesn't leak onto everything else in the bag, and your snacks stay fresh.
We stock sauce pots from 1oz (28ml) up to 12oz (350ml) — all BPA-free, microwave and freezer safe, with secure lids. The smaller sizes are ideal for dressings and condiments; the larger sizes work well for dips, hummus, or overnight oats.
Plastic vs Glass Food Containers: Which Is Better for Meal Prep?
Glass containers are heavier, more expensive, and more fragile than plastic — but they don't absorb odours or stains, they're oven-safe (most plastic isn't), and many people prefer them for long-term storage. For meal prep that involves carrying containers to work or the gym, the weight and fragility of glass is a practical drawback. For home batch cooking and fridge storage where weight doesn't matter, glass is a reasonable choice.
For most people doing regular weekday meal prep — prepping on Sunday, carrying containers to work Monday through Friday — good quality BPA-free plastic is the more practical answer. It's lighter, more durable for daily use, and significantly cheaper per container, which matters when you're buying a full set of 10 to 20 containers at once.
Where to Buy Leak-Proof Food Containers Online in the UK
Supermarkets stock a limited range of food containers, usually in small pack sizes at relatively high per-unit prices. For anyone buying a full set of meal prep containers — or stocking up for a household that preps regularly — buying online in multi-packs is significantly better value.
At Reign Goods, all our plastic food containers are available in multi-pack quantities with free tracked delivery on orders over £30 and same-day despatch before 4pm. Browse the full range:
- 500ml rectangular containers with lids
- 650ml rectangular containers with lids
- 1000ml rectangular containers with lids
- 24oz round meal prep containers
- 32oz round meal prep containers
- 48oz round meal prep containers
- Sauce pots and small containers with lids
Frequently Asked Questions
What are the best reusable food containers for meal prep in the UK?
BPA-free plastic containers with secure lids, microwave-safe and freezer-safe ratings, and dishwasher-safe construction are the practical standard for meal prep. For most adults, a mix of 650ml and 1000ml rectangular containers covers the majority of lunch and dinner portions. Reign Goods stocks the full size range with free UK delivery on orders over £30.
Are plastic food containers safe to use in the microwave?
BPA-free polypropylene (PP) plastic containers are microwave-safe when used as directed. Always check for the microwave-safe symbol on the base of the container. All plastic food containers stocked at Reign Goods are BPA-free and microwave-safe.
What size food container do I need for meal prep?
For a standard adult lunch portion — rice, pasta, or a similar meal — a 650ml container is usually sufficient. For larger appetites or protein-heavy gym meals, 900ml to 1000ml is more appropriate. Sauce pots in the 60ml to 120ml range are useful for dressings and dips.
Where can I buy leak-proof food containers online in the UK?
Reign Goods stocks a full range of leak-proof, BPA-free food containers with lids in multiple sizes, available online with free tracked delivery on orders over £30 and same-day despatch before 4pm.
Are food containers with lids freezer-safe?
All the food containers stocked at Reign Goods are freezer-safe as well as microwave-safe — meaning you can prep, freeze, and reheat in the same container without transferring food between dishes.