What are permanent stamps actually worth?

[luknis_0]

I need some clarification on what permanent stamps are actually worth, because every answer I’ve found is as clear as mud.

So, currently, P stamps are $0.90 in booklets/coils, and $1.05 individually.

I am aware that they are good to send a regular >30g letter, but,

When I use them on oversized lettermail, what is their value? $0.90 or $1.05? If I’m mailing oversized lettermail that is less than 100g, ($1.90), do I need 2 permanent stamps or 3?

Thank you.

[mcrlmn · Accepted solution]

'Permanent' (P) stamp value is 90¢... period.

If you required $1.90 postage, you would need  2 'P'  stamps + a 10¢ stamp.

90¢ + 90¢ + 10¢ = $1.90