How long does powdered formula last once opened?

[Caspianberg]

And is there a way of working out how many oz you would get from one box?

I'm looking into options. Would like to Breastfeed most feeds but give a small bottle of formula per day so Dh can easily take over. Happy for it to be formula rather than express.

Need around 4-5 oz per day.

The box of 800g Hipp is €9 here, a single serve ready made is €1.60!. Im assuming I will get way more than 8 bottles worth from a tub so it would far better cost wise.

Would one box last roughly a month of just one feed per day? I see it says any opened formula should be thrown after one month, is this coorrect?

If I remember rightly the SMA tub was 180 scoops at one scoop per ounce they do last and are significantly cheaper than ready made. Ready made does have different ingredients it in which some babies don't like. My 11 month old can taste the difference. My HV did say ready made was good if they are constipated though!

Ok may have just workd it out myself. 1 scoop is 4.5g apparently on average. 800g/4.5g= 177.7. 177.7/5oz = 35.5.

So one box should last over a month if making 5oz bottles, more if 4oz. So would I have to just throw away the powder left after 30 days and open a new box? how does the powder go off if it isnt sterile in the first place?

@user159 - you seem correct with the 180 scoops! thanks