The short version: your campaign cadence is a formula, not a folk number. The customer's repurchase cycle sets the base (fast-consumable lists tolerate and reward roughly three sends a week; furniture lists want one), the season multiplies it (pre-season and BFCM up, off-season down), and your team's capacity to produce genuinely good emails caps it, because a mediocre send costs engagement that a skipped send does not. The published guidance brackets the sane range: two to four campaigns per month suits most ecommerce businesses, one to three weekly emails maintains engagement without burnout, and promotional sends specifically should stay to once or twice a week. The calculator below runs our formula on your inputs; the rest of the post is the reasoning, so you can overrule it intelligently.
Use the calculator
Answer four questions and get a monthly cadence with its weekly rhythm. The output assumes you will fill the slots with the four-job rotation (value, proof, product, community) from our content calendar SOP rather than pure promotion.
Why repurchase cycle is the base variable
Email frequency tolerance tracks purchase frequency. The customer who buys coffee every three weeks has a live commercial relationship with the category most days of the month: three sends a week can all be relevant. The customer who bought a sofa has a live relationship for a few weeks a year: the same three sends a week are two and a half sends of noise, and noise is what unsubscribes are made of. That is why the calculator's bases run from roughly twelve sends a month for under-30-day cycles down to four for multi-year cycles, and why borrowing another brand's cadence is the most common frequency mistake: the number that works is downstream of how often your customer is actually in-market.
The season multiplier
Cadence is not a constant. Pre-season windows and BFCM support half again the normal volume because relevance is temporarily universal (the BFCM adjustments govern that window in detail), and off-seasons support barely more than half of normal, shifted toward the value and community jobs, per the season-block profiles in the calendar SOP and the seasonal architecture. A fishing brand running July's cadence in January is teaching its list to stop opening before the season that matters.
The capacity cap, and why it wins ties
The formula's third input outranks the other two whenever they conflict: never send more emails than your team can make genuinely good. A send exists to earn a click, and a filler email spends list attention (and sender reputation, which is engagement-scored) to earn nothing. If the cycle math says twelve and your team can craft eight, the answer is eight. Volume is recoverable next month; a list taught that your emails are skippable is not.
The guardrails: how you know the cadence is wrong
- Unsubscribe rate against the norm: average ecommerce unsubscribe rates run 0.20 to 0.30% per send, with well-managed Klaviyo accounts baselining near 0.21%. A climbing trend is the cadence (or the content ratio) talking.
- The frequency ceiling nobody should test: sending more than one promotional email per day doubles unsubscribe rates, and over 30% of unsubscribers name too many emails as their reason for leaving.
- Click reach, not opens: the share of your engaged segment clicking anything across 30 days. Falling click reach at rising volume is the definition of fatigue, and opens cannot be trusted for this per the MPP inflation problem.
- Cut frequency before quality: when the guardrails trip, drop the weakest slot from the rotation, never the craft from the remaining sends.
Campaigns are the variable layer, not the engine
One framing note before you turn the dial: cadence optimizes the smaller revenue lever. Campaigns are 94.7% of email sends but flows generate nearly 41% of email revenue from the other 5.3%, so if your flow stack is incomplete, an hour spent there beats a cadence debate every time: the flow stack guide and audit checklist are the higher-leverage reads. Cadence matters once the floor is built.
Frequently asked questions
How many marketing emails should an ecommerce brand send per month?
Most brands land between 4 and 12 campaigns per month: repurchase cycle sets the base (fast consumables high, considered purchases low), season multiplies it, and team capacity caps it. The published consensus band is 1 to 3 sends per week with promos held to 1 to 2.
Is sending more emails always more revenue?
Short-term, usually; sustainably, only up to the relevance limit. Past it, unsubscribes and fatigue compound: more than one promo per day doubles unsubscribe rates, and 30% of unsubscribers cite volume as their reason.
Should every send be promotional?
No: hold promos to one to two per week inside the four-job rotation. The non-product sends are what keep engagement healthy enough for the product sends to convert.
How do seasonal brands set cadence?
Three profiles, not one number: pre-season and peak at roughly 1.5x the base, normal at base, off-season near 0.6x shifted toward value and community content.
What signals say the cadence is too high?
Unsubscribes trending above the 0.2 to 0.3% norm, falling 30-day click reach, and rising spam complaints. Respond by cutting the weakest slot, not the quality of the rest.
Sources
- Omnisend. Email marketing frequency guidance.
- Opensend. Ecommerce unsubscribe rate statistics.
- Klaviyo. Email marketing benchmarks.
- Mailflow Authority. Apple Mail Privacy Protection and open rate inflation.