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Syns & Slimming World

How Many Syns in Custard?

By Jenny Updated

Custard is one of those quintessentially British comforts that turns any pudding into a proper treat, and the good news for Slimming World members is that it can absolutely have a place on your plan when you portion it sensibly. Fresh chilled custard from the supermarket chiller cabinet typically clocks in at around 3.5 Syns per 100g, which makes a generous splash over a Hi-fi bar crumble or a baked apple a perfectly reasonable indulgence. It is not Free, and it cannot be counted towards your Healthy Extra A allowance either, because despite containing milk it sits firmly in the treats category thanks to the added sugar and thickeners.

The Syn value of custard varies enormously depending on the format you choose, so it pays to read the back of the pot before you pour. Tinned ready-to-serve custard tends to be slightly lower in Syns than the luxury fresh chilled versions, while powder mixed with skimmed milk can be one of the lighter options if you skip the added sugar. Low-fat varieties and reduced-sugar lines have proliferated in recent years, giving members far more flexibility than the single pouring jug of the nineties ever did.

To keep things sensible, weigh your portion rather than eyeballing it. A 100g splash over fruit feels generous when paired with a mountain of berries or stewed rhubarb sweetened with granulated sweetener, and a 150g serving covers a proper pudding bowl. Pair custard with Free fruit bases like baked plums, poached pears or a hot bramley apple to bulk out the bowl, so the Syns you spend deliver maximum pleasure. Whisked into a low-Syn trifle with sugar-free jelly and Muller Light yogurt, custard becomes the backbone of a brilliant family pudding without derailing your week.

Per serving

Custard — syn values

Portion Syns kcal
1 tbsp (15g) 0.5 14
50g splash 2 47
100g (fresh/chilled) 3.5 93
125g portion 4.5 116
150g serving 5.5 140
200g large bowl 7 186
Syn values are based on Slimming World 2026 guidance. Always double-check with your group or app.

Numbers at a glance

Quick auto-calculated stats for Custard.

3.3syns / 100g
Syns per 100g
useful for comparing brands
3%
of a 15-syn day
based on standard daily allowance
28kcal / syn
calories per syn
the lower, the more 'value' your syns get
6
portion sizes covered
from snack to full serving
0.5syns
cheapest portionat 1 tbsp (15g)
smallest serving

Brand breakdown

Popular supermarket and branded products, with the portion-level syn count.

Brand Product Portion Syns kcal
Ambrosia Devon Custard (tinned) 100g 4.5 97
Ambrosia Light Custard 100g 3 74
Ambrosia No Added Sugar Custard 100g 3 69
Bird's Original Custard Powder (made with skimmed milk, no sugar) 100g made up 2.5 55
Tesco Fresh Custard 100g 5.5 118
M&S Madagascan Vanilla Fresh Custard 100g 6 131
Alpro Soya Custard Alternative 100g 3 71
Sainsbury's Reduced Fat Fresh Custard 100g 4 91

Lower-syn alternatives

Swaps that keep the feel of the original without the syn hit.

Muller Light vanilla yoghurt

Free

A Muller Light vanilla yoghurt gives you a sweet, creamy topping for fruit and puddings at zero syns. While it lacks the warm, velvety richness of custard, it satisfies the same creamy-sweet craving and saves you the 3.5 syns per 100g.

Bird's custard powder with skimmed milk (no sugar)

2.5 syns per 100g made up

Making custard from Bird's powder with skimmed milk and sweetener instead of sugar is one of the lightest custard options at about 2.5 syns per 100g. It saves roughly 1 syn per 100g compared to standard fresh custard and you control the sweetness.

FAQs

How many syns in custard?

Fresh chilled custard is around 3.5 syns per 100g, while a 150g serving costs about 5.5 syns. Ambrosia tinned custard is slightly higher at 4.5 syns per 100g, but their Light and No Added Sugar versions drop to about 3 syns per 100g. Bird's powder made with skimmed milk and no sugar is one of the lightest at 2.5 syns per 100g.

Is custard free on Slimming World?

No, custard is not free on Slimming World. The added sugar and thickeners mean it must be synned, typically around 3.5 syns per 100g for standard fresh custard. It does not count towards your Healthy Extra A either. However, at a manageable syn cost, a measured splash over fruit makes a sensible treat.

What is the lowest syn custard?

Bird's Original Custard Powder made with skimmed milk and no added sugar comes in at about 2.5 syns per 100g made up, making it one of the lightest options. Ambrosia Light and No Added Sugar custards are also good at roughly 3 syns per 100g. Avoid premium fresh custards which can climb to 6 syns per 100g.

Can you have custard on Slimming World?

Yes, custard fits well into a balanced Slimming World day. A 100g splash at 3.5 syns poured over Free fruit like baked apple, stewed rhubarb or fresh berries makes a comforting pudding. Weigh your portion rather than free-pouring, and choose light or no-added-sugar versions to stretch your syns further.

Lower-syn dairy alternatives

Food Portion Syns vs current
Greek Yogurt 0% Fat 170g (Fage 0%) FREE −0.5 syns

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