Ninaandaa bajeti; mpango wa matumizi una gharama za lazima.

It breaks down like this:

• ni- = I
• -na- = present tense marker
• andaa = prepare

So ninaandaa means I prepare / I am preparing.

You see aa because the tense marker is followed by a verb stem that begins with a:
ni-na-andaa.

It can mean either, depending on context.

In Swahili, -na- often covers both:

• a general present: I prepare
• a current action: I am preparing

In this sentence, I am preparing is the most natural interpretation, but the form itself can do both jobs.

Bajeti is a loanword, ultimately from budget. This is very common in Swahili, especially for modern administrative, financial, and technical vocabulary.

So even though it looks similar to the English word, it is a normal Swahili word in use.

Literally, mpango wa matumizi is something like plan of spending/use.

Parts:

• mpango = plan, arrangement
• matumizi = use, usage, spending, expenditures
• wa = a linking word meaning of, agreeing with mpango

A very important point: wa agrees with the first noun, mpango, not with matumizi.

So:

• mpango wa matumizi = plan of spending / spending plan

Here, matumizi refers to spending, expenses, or expenditures.

It comes from the verb tumia, which means use or spend.
So depending on context, matumizi can mean:

• use
• usage
• spending
• expenditure(s)

In a budgeting sentence, the financial sense is the one you want.

Yes, una can mean you have in another context. But here it does not mean that.

In this sentence, the subject is mpango wa matumizi. Since mpango belongs to the m-/mi- noun class (singular class 3), the verb agrees with it using u-.

So una here means:

• it has
• it contains

That is why mpango wa matumizi una ... means the spending plan has ..., not you have ....

Gharama za lazima means necessary costs/expenses or required expenses.

Parts:

• gharama = cost, expense, expenses
• za = linking word meaning of/that are, agreeing with gharama
• lazima = necessary, required, obligatory

So the phrase is literally something like expenses of necessity.

English usually turns that into necessary expenses.

Swahili often expresses ideas that English uses adjectives for by using a noun plus a connector.

So instead of a simple adjective pattern, you often get something like:

• gharama za lazima = expenses of necessity = necessary expenses

This is a very normal Swahili way of building descriptions.

Swahili does not have articles like English a/an and the.

That means a noun like bajeti can mean:

• a budget
• the budget

The exact English choice depends on context. The same is true for mpango wa matumizi.

Not exactly.

• bajeti = budget
• mpango wa matumizi = spending plan / expenditure plan

In real life, they can overlap a lot, but the emphasis is slightly different:

• bajeti focuses on the budget as a whole
• mpango wa matumizi focuses on how money will be used

So the second phrase helps explain or expand on the first idea.

The semicolon links two closely related clauses:

• Ninaandaa bajeti
• mpango wa matumizi una gharama za lazima

It shows that the second clause is closely connected to the first one. In English, it works a lot like a strong comma or a soft full stop.

You could also separate them with a full stop, but the semicolon makes the connection feel tighter and slightly more formal.