At what quantity does offset become cheaper than digital?

There is no universal quantity. It depends on your rates: divide the difference in fixed costs (offset plates and makeready minus digital setup) by the per-sheet saving (digital click minus offset run cost, times sides). With typical small-shop rates the answer lands in the low thousands of sheets.

Can offset ever fail to break even?

Yes. If the digital click cost is at or below the offset run cost per impression, offset starts with higher fixed costs and never recovers them. In that case digital is cheaper at every quantity.

Is the break-even measured in sheets or impressions?

The division yields press sheets. Multiply by the number of printed sides to express it as impressions, and by the n-up count to express it as finished pieces. Mixing these units up is a common estimating spreadsheet bug.

Does paper cost affect the digital vs offset choice?

Usually not the choice itself, because both routes print the same sheets on the same stock. It affects the total price, but it cancels out of the comparison unless the two routes would run different sheet sizes or spoilage.

Choosing digital vs offset printing

Digital printing wins short runs and offset wins long runs. Digital has almost no setup cost but a higher cost per impression; offset pays for plates and makeready up front and then runs cheaper per sheet. The break-even point is where offset's fixed costs are amortized: divide the difference in fixed costs by the difference in per-impression cost. Below that sheet count, print digital; above it, offset.

The cost structures

A digital press charges per click: every impression costs roughly the same, whether it is the first or the ten thousandth. Setup is minutes of operator time.

An offset press pays a fixed cost before the first good sheet: one plate per ink color per printed side, plus base makeready time to mount plates, set ink keys, and run up to color. After that, the cost per impression is low, mostly paper, ink, and press time.

Finding the crossover

The crossover in sheets equals the offset fixed cost minus the digital fixed cost, divided by the per-sheet saving of offset. The per-sheet saving is the digital click rate minus the offset run rate, multiplied by the number of printed sides.

Worked example: offset fixed cost of $300 (base makeready plus 8 plates), digital setup of $30, digital click of $0.04, offset run cost of $0.01, printed both sides. The saving is $0.06 per sheet, so the crossover is 270 divided by 0.06, which is 4,500 sheets. Below 4,500 press sheets the job is cheaper digital; above it, offset.

If your digital click rate is at or below your offset run rate, offset never breaks even at those rates: it starts behind on fixed cost and never catches up per sheet. That is a real answer, not an error.

What the math does not capture

Cost per sheet is not the whole decision. Variable data and versioning are digital-only. Tight color matching to a brand standard, metallic and spot inks, and very large sheets favor offset. Turnaround favors digital on anything small. Substrate range differs by press. The calculation narrows the choice; the shop's equipment and the job's requirements finish it.

Put the numbers to work in the PressBench estimator, or check the reference tables.