If multiple shareholders of the startup Scorp are making weekly $500/$1,000 investment/deposit into the company’s business account for a few months during the first year of business, is any of it taxable? Is there any CAP on shareholders investments that’s non-taxable?is there any other form other than the balance sheets that is needed to be kept? And is there any difference with this situation in Scorp and Ccorp?
Equity infusions by the stockholders/members are considered to be capital contributions and as such are not income or taxable. The contributed amounts increase the stockholder/members equity balance in the company.
Note that these cash infusions could also be considered loans to the corporation. In this case, the cash would be recorded as "Loans from shareholders" instead of paid-in capital.
If the corporation documents do not limit the amount of equity available in the company, there is no cap on total contributions. It is prudent for the company to keep good records of all equity transactions, tracking activity by shareholder/member to avoid disproportionate allocations of income/loss and distributions in excess of basis.
Equity transactions are basically the same for C-Corps and S-Corps.