A chosen deduction reduces the cash that can buy shares.
With assumed gross cash of $100, a chosen $1 deduction and a hypothetical $25 purchase price, the remaining $99 buys 3.96 modeled shares. With a zero deduction, the same gross buys 4 shares. This is a controlled sensitivity test, not a claim that Schwab or your broker charges a reinvestment fee. It excludes taxes, price movement and share rounding.
The existing SCHD DRIP cash-to-shares audit starts from the cash actually reinvested. Here we expose one possible adjustment before that division. Use documented statement amounts for a real reconciliation; a missing charge is not permission to invent one.
Declare the deduction before doing the division
The fixture uses three independent inputs, all in USD: gross cash C, chosen nonnegative deduction F, and positive execution-price assumption P. It subtracts F from C once on each declared row and divides the remainder by P. This is an isolated cash-allocation rule, not an account agreement, order execution or fund-expense model.
For C = $100, F = $1 and P = $25 per share, net cash N = C − F = $99 and modeled shares Q = N ÷ P = 99 ÷ 25 = 3.96. The cash identity is $99 invested + $1 deducted = $100 supplied. With F = $0, Q = 100 ÷ 25 = 4. The difference is 4 − 3.96 = 0.04 share, also equal to the chosen deduction divided by price: 1 ÷ 25.
That 0.04 share is a model difference at the same assumed price, not a cash dividend that disappeared. The $1 is still accounted for in the deduction column. Treating all $100 as invested while also recording $1 as deducted would allocate $101 from a $100 starting amount. The conservation check rejects that interpretation.
Four deductions are not one deduction
Assume four independent receipts of $100 each and the same chosen $1 deduction on every row. Gross cash sums to $400, deductions sum to $4, and investable cash sums to $396. Holding the hypothetical price at $25 on all four rows gives 4 × 3.96 = 15.84 modeled shares. The row count is an input to this fixture, not an assertion of actual future payments.
A different contract that subtracts $1 only once from the combined $400 leaves $399, buying 399 ÷ 25 = 15.96 shares. Compared with the four-deduction contract, that is $3 more investable cash and 0.12 more share. The arithmetic isolates charging frequency; it does not recommend pooling payments or assert that the price would stay fixed while waiting.
What happens at zero or with missing data?
| Case | Net USD | Shares or state |
|---|---|---|
| chosen_fee | 99 | 3.96 |
| zero_fee | 100 | 4 |
| cash_equals_fee | 0 | 0 |
| zero_cash_fee | 0 | 0 |
| fee_above_cash | Unknown | deduction_exceeds_cash |
| missing_fee | Unknown | unknown_input |
| missing_cash | Unknown | unknown_input |
| missing_price | Unknown | unknown_input |
| zero_price | Unknown | invalid_input |
Download the assumed inputs · Download exact outputs and rejection cases
If gross cash and deduction are both explicitly zero and price is a valid $25, net cash and modeled shares are zero. If gross cash is $1 and the chosen deduction is also $1, the remainder is zero and the model buys zero shares. This is a fully depleted arithmetic row, not a claim that a broker executes or charges for a zero-share order.
If gross cash is only $0.50 while the deduction is $1, the fixture returns deduction-exceeds-cash status. It does not silently borrow the missing $0.50, sell holdings, turn net cash negative or clamp it to zero while pretending the full charge was funded. A different financing rule would need a separately specified source of cash.
Missing gross, fee or price inputs return unknown-input status. Negative cash or deduction and a zero price are invalid. Under this intentionally strict test, price must be positive even when net cash would be zero. That is a validation choice; it keeps incomplete execution assumptions distinct from a verified zero result.
Keep price sensitivity separate
At a different chosen price of $20, the same $99 net cash buys 4.95 shares rather than 3.96. The difference of 0.99 share comes from the changed price, while the deduction remains $1. Comparing that result with the no-deduction $25 scenario would change two inputs at once. The downloadable cases keep cash, deduction and price in separate columns so the source of each difference stays visible.
Is this SCHD's expense ratio or a real broker charge?
No. The SEC's fee bulletin distinguishes transaction charges from ongoing expenses and directs readers to disclosures and account records. This page uses a deliberately chosen cash deduction. It does not take a fund expense ratio and subtract it again from a published distribution. A real fee, exemption or charged frequency needs the applicable account terms.
Why model a charge that might be zero?
A public reinvestment discussion raises trading costs as one factor in manual-versus-automatic reinvestment. The reader's reported charges are not verified or adopted here. A zero-fee branch makes the question testable without assuming everybody pays the same amount. The worksheet compares cash arithmetic, not which reinvestment choice you should make.
Evidence and scope
Reviewed October 25, 2026. Investor.gov supports the fee categories and need for documentary verification; all cash, fee and price numbers in this article are explicit assumptions. Decimal and exact-fraction checks reproduce each valid case. Fresh reads of the three fixed calculator pages inform the comparison scope, not the inputs. This particular conservation and fee-frequency fixture is the independently calculated addition, not a statement of whole-web originality.