Split shifts have a terrible reputation among the people who work them, and an excellent one among the people who watch costs. Block shifts, the exact opposite. The discussion usually stops there, as a war of preferences. But the choice between the two is not ideological: it depends on the shape of your day, on where your team lives, and on what you are willing to give in return. It deserves to be remade with numbers every so often, instead of dragging along as habit.
The shape of demand decides half the answer
A store with two sharp humps (11 to 1, and 5 to 7) and a crater in between is the natural candidate for splits: paying full staff at 3pm to stare at the ceiling helps nobody, morale included. A flat curve, or a single hump, tells the opposite story: there, splits are just discomfort inflicted with no return.
The point is to actually know your shape. Receipts per time slot over a typical month: half an hour of work, and no opinion can dress up as data anymore.
The cost of the split is not on the payslip
Splits cost the people who work them: two commutes, a long gap that is not real free time (too short to go home, too long for a coffee), a day that stretches to ten hours to get paid for six. That invisible cost gets paid regardless, just elsewhere: in declined job offers, in turnover, in mood.
So whoever uses splits has to compensate somehow: rotate them instead of always assigning the same people, give first pick of days to those who accept them, notice who lives two minutes away (for whom the split is cheap) versus who commutes forty. And there is a minimum pact of seriousness: if the split exists to cover peaks, the two fragments must actually land on peaks. Splitting the day and then having people idle at 3pm is the worst of both worlds.
Blocks have holes of their own to face
With blocks the risk is symmetrical and quieter: overstaffing through the empty hours and, often, a changeover placed at a delicate time. If the handover falls at 5pm in the middle of the evening climb, the store pays for its blocks with a hole exactly where it could least afford one. Sometimes staggering start times is all it takes (not everyone at 9-3 and 3-9, but also 10-4 and 4-10) to keep the block's advantages without the changeover hole.
Decided? Now explain it
Whatever the outcome, the step almost everyone skips is telling the team why: "splits on Friday and Saturday because these are the numbers, blocks the rest of the week, we review in six months". The same choice, with its criterion declared, is experienced completely differently: no longer an arbitrary imposition but a rule with a logic, contestable with numbers rather than grumbling.
When the choice is about a repeating cycle rather than a single day, the reasoning changes: it is in 6x2, 5x2 and shift rotation patterns.
Trying both configurations on your own data (coverage per slot, paid hours, resulting holes) is the fastest way to close the debate: with Sked Solve you can compare plans before publishing them, as the site shows.