Hello and welcome to the site. Thank you for your question.
If you are employing freelancers, then I presume they are self employed and would account for their tax and NI when filing their personal tax returns.
if this is the case, then you don't have to factor anything for their tax and NI.
You say your profits before tax are £105,000.
Taking a salary of say £30k would mean you would be paying NI as follows:
Employer £3.042 (less £2,000 allowance)
Both of these costs are avoidable if you were to reduce your salary to£7,944 and take the rest in dividends as dividends do not attract Nat Ins contribution.
Dividends are distribution of taxed profits.. i.e after corporation tax on profits.
Based on your figures, your profit after tax would be 105,000-(105,000x20%) =£84,000.
Dividends are payable out of this figure...
If your total income including dividends exceeds £41,865 then dividends would attract tax rate of 32.5%, effectively you pay tax at 25% of dividends received after taking into account tax credit.
More information on dividend tax credit can be found here
I hope this is helpful and answers your question.
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