The Real Cost of Spam: Time, Attention and Money

SPAM AND INBOX OVERLOAD

The Real Cost of Spam: What Junk Mail Takes From Your Time and Attention

Ask someone what spam costs them and they’ll describe deleting it. A few seconds a message, a mildly irritating chore, nothing worth writing an article about. That answer is wrong in an interesting way: the deleting is real but trivial, and it sits on top of four other costs that are considerably larger and almost entirely invisible.

Here’s the full bill.

01 The cost everyone names, which is the small one

Let’s give the obvious answer its due and then set it aside honestly.

Dismissing a junk message takes a second or two. Modern filtering is genuinely good, so most of what’s sent to you never reaches your inbox at all. If the only thing spam cost was the muscle movement of deleting it, the problem would be roughly as serious as junk mail through a letterbox — annoying, and solved by a bin.

Work out your own figure if you like: messages you dismiss in a day, multiplied by two seconds, multiplied by 365. Most people land somewhere between a couple of hours and a working day per year. That’s not nothing, but it isn’t the story, and articles that stop here are measuring the cheapest component because it’s the easiest one to measure.

02 The interruption, which is the expensive one

The deletion is cheap. Getting pulled out of what you were doing is not.

Research on workplace interruption by Gloria Mark at the University of California, Irvine is the work usually cited here, and the headline figure — that it takes something like 23 minutes to return to a task after being interrupted — has become one of the most quoted numbers in productivity writing.

Even read conservatively, the implication is uncomfortable. A notification for a message that turns out to be junk costs you the notification, the glance, the assessment, the dismissal — and then the considerably longer tail of getting back to where you were. The two seconds of deleting is the only part you notice.

This is also why spam is worse on a phone than on a desktop. A push notification arrives during whatever you were actually doing, and there is no filtering step between the arrival and the interruption.

03 The vigilance tax

The third cost is subtler and, over years, probably the most corrosive.

Every unfamiliar message in your inbox requires a small judgement: is this real? Most of the time the answer is obvious within a second. But the judgement still happens, thousands of times a year, and it has two effects that pull in opposite directions.

The first is simple depletion. Adjudicating a stream of low-stakes decisions is tiring in a way that’s hard to attribute afterwards, because no individual decision felt like work.

The second is worse. When nearly everything suspicious turns out to be harmless clutter, the habit you build is fast dismissal — and fast dismissal is precisely the reflex a well-made phishing message is designed to exploit. Spam trains you, message by message, to be the sort of person who doesn’t look closely. The volume of junk is what makes the rare dangerous message survivable for the attacker.

04 The money, which is measurable

Which brings us to the part with hard numbers attached. The FBI’s Internet Crime Complaint Center publishes an annual accounting of reported losses in the United States, and the 2025 report, released in April 2026, is sobering.

Figures from the FBI IC3 2025 Internet Crime Report. US-reported complaints only — actual losses are certainly higher, since most fraud goes unreported.

Narrow it to the categories that specifically exploit trust in email and the picture stays severe. Business email compromise at $3.04 billion, phishing and spoofing at $215.8 million across roughly 191,000 complaints, and government impersonation at $797.9 million together exceed $4 billion in a single year.

Two details deserve attention. Phishing and spoofing losses rose sharply — a 208% year-on-year increase — even though complaint volume stayed roughly flat, meaning the average attack got substantially more profitable rather than more common. And the report included AI-related fraud for the first time: 22,364 complaints and close to $893 million.

It’s fair to object that most of this is fraud rather than spam in the newsletter sense. That’s true, and it’s the point. Fraud arrives through the same channel and hides in the same volume. A quiet inbox makes an unexpected invoice conspicuous; a noisy one makes it ordinary.

05 The mail you never saw

The last cost is the one you cannot audit, because its nature is that you don’t know it happened.

Filters make a trade-off. Tuned aggressively enough to catch the junk, they will sometimes misfile legitimate mail — an invoice, an interview invitation, a delivery notice, a message from someone writing to you for the first time. These land in a folder nobody enjoys reading, and a consequential one can sit there until it stops mattering.

This is a direct consequence of volume. If ten junk messages reached you a week, no aggressive filtering would be needed and false positives would be rare. Filters are set as tightly as they are because the tide is as high as it is — so the cost of missed mail is properly counted as a cost of spam, not a failing of the filter.

The bill, itemised

Only the top row is easy to measure, which is exactly why it dominates the conversation.

Why filters can’t finish the job

Spam filtering is one of the quiet triumphs of modern computing. It removes the overwhelming majority of what’s aimed at you and asks nothing of you in return.

But look at the itemised list and notice which costs a filter actually removes. It reduces deleting time. It reduces some interruptions. It does nothing about the false positives it creates by existing, and — crucially — it cannot help with the messages that are designed to look legitimate, because those are the ones built specifically to pass it.

A filter is a treatment for the symptom. It cannot reduce how many lists your address appears on, and that number only ever rises.

What actually reduces the bill

The only lever that moves all five costs at once is how much junk reaches an address you actually read.

That isn’t achieved by filtering harder. It’s achieved by not giving a permanent address to senders who have no durable reason to reach you — which is a decision made at the sign-up form, seconds at a time, and compounds over years.

It’s worth being honest that this is slow. Lists already holding your address will keep it forever, so an inbox that’s been public for a decade won’t go quiet next month. What changes is the direction of travel: new lists stop acquiring you, and the curve flattens instead of climbing.

Frequently asked questions

How much does spam actually cost people?

Financially, the measurable damage is large. The FBI’s Internet Crime Complaint Center recorded close to $21 billion in total reported losses across more than a million complaints for 2025, and the categories that specifically exploit trust in email — business email compromise, phishing and spoofing, and government impersonation — together account for over $4 billion of that. BEC alone reached $3.04 billion, averaging more than $122,000 per complaint.

Is deleting spam really a big time cost?

Deleting is the smallest of the costs. Each message takes a second or two, and modern filters catch most junk before you see it. The expensive parts are what surrounds the deletion: the interruption that pulled you out of what you were doing, and the judgement you make about whether each unfamiliar message is safe.

Why does spam make me worse at spotting real phishing?

Because constant low-stakes false alarms train you to dismiss quickly rather than assess carefully. When almost everything suspicious turns out to be harmless clutter, the habit you build is fast dismissal — and that habit is exactly what a well-made phishing message needs to slip past you.

Do spam filters have a hidden cost?

Yes — false positives. A filter aggressive enough to remove most junk will sometimes misfile legitimate mail, and an invoice or interview invitation sitting unseen in a spam folder can cost far more than any amount of junk in your inbox. The cost is invisible by nature: you don’t know about the message you never saw.

What actually reduces the cost of spam?

Reducing how much of it arrives at an address you actually read. Filters manage the symptom; compartmentalisation addresses the cause. A permanent address for correspondence that matters, aliases for services you keep, and disposable inboxes for one-time sign-ups keeps your everyday inbox quiet enough that an unexpected message is worth a second look.

The bottom line

Spam is usually filed under annoyances, and annoyances are things you tolerate. The itemised bill says something different: a chronic tax on attention, a slow erosion of the judgement you’d need to catch a real attack, and a channel through which more than four billion dollars moved out of people’s accounts in a single year.

You can’t stop people sending it, and you can’t retrieve an address already circulating. What you can decide is how many of them get a line that rings on a phone you carry — and that decision is made a few seconds at a time, at forms you fill in without thinking.