I have different iCloud IDs for my iPhone &Mac and I have 5GB on each, if I decide to use only 1 ID for both, can I have 10GB or will I be limited to 5 since it's 1 iCloud ID.

I have different iCloud IDs for my iPhone &Mac and I have 5GB on each, if I decide to use only 1 ID for both, can I have 10GB or will I be limited to 5 since it's 1 iCloud ID. I am afraid that if I I use only 1 iCloud ID for both of them I will be limited to only 5GB which is small a nd I don't have money to be paying annually for extra GB. Thanks and waiting for your replies.