Summary
How much does it cost to send a letter to wholesale customers? A PostNL stamp costs €1.40 and a UK first class stamp about €2.10 in 2026. A WhatsApp marketing message in the Netherlands carries a Meta fee of about €0.13, plus a platform fee. On fees alone WhatsApp is cheaper per contact and adds measurement and replies. Letters still win for formal notices.
TL;DR
- Per 1,000 contacts, PostNL stamps cost €1,400 alone, against about €130 in Meta fees for WhatsApp marketing messages. The platform fee comes on top: from €119 per month for Saysimple's Grow plan (€178 with Broadcasting).
- WhatsApp shows sent, delivered and, with read receipts on, read statuses per message. A letter gives you no signal at all.
- Replies land in one shared inbox instead of on a phone number at the bottom of a letter.
- Keep the letter for formal notices, customers who have not opted in and anyone who expects paper.
Price lists, order notices, invoice reminders, a mailing for the autumn promotion: if your wholesale business still sends those by post, the cost adds up faster than most people expect. This article is a business case for that situation. It makes no claim about how many wholesalers still post letters.
If you searched for how much it costs to send a letter, you probably want one number: the stamp. In 2026, a PostNL standard stamp costs €1.40 for a letter or card up to 20 g. For a wholesaler that is only the start, because you pay it for every customer and every mailing, and nothing comes back that you can measure.
This article puts the letter next to a WhatsApp message on three points: cost per contact, measurability and the chance to reply right away. We stay with that comparison. What Meta charges per message category, and what changes for service messages from October 2026, is covered in what WhatsApp messages cost from October 2026. The cost layers of WhatsApp Business for wholesalers are in WhatsApp Business pricing for wholesale owners.
How Much Does It Cost to Send a Letter in 2026?
PostNL charges €1.40 for a standard stamp on a letter or card up to 20 g, a price that has applied since 1 January 2026. It stays €1.40 from 12 July 2026, when letterbox mail is delivered within two delivery days as standard. That stamp price is the number most people look for.
The stamp is only the visible part of direct mail cost. Each letter also needs printing, an envelope and the time to fold, seal and stamp it. Those three differ per company, so we don't fill them in for you.
One caution: the stamp is the consumer price. Businesses that post in volume usually pay less, for example with PostNL's business contract rate (the "zakelijk" tariff) or, in the UK, Royal Mail Mailmark franking. Use your own rate and work with this: number of letters × (your rate per letter + printing + envelope + handling time).
Here is the maths at the stamp price. 1,000 letters × €1.40 = €1,400 in stamps. Send a price list to 1,000 customers every quarter and that is €5,600 a year in stamps, before printing, envelopes and handling time.
Posting in the UK instead? Royal Mail charges about €2.10 for a first class stamp, about €1.05 for second class and about €1.80 for a second class large letter (up to 100 g), since 7 April 2026. These amounts are converted at roughly €1.16 per pound, a rate seen in August 2026, so check the live exchange rate and Royal Mail's own tariff. Mailmark franking can bring the price per letter below the stamp.
What Does a WhatsApp Message to a Wholesale Customer Cost?
Meta sets the price of a message by two things: the message category and the country of the recipient. For customers in the Netherlands, a marketing message costs about €0.13 and a utility message about €0.04. For customers in the UK, a marketing message runs roughly €0.05 to €0.09, and sources differ on the exact figure. A price list or promotional mailing counts as marketing. An order confirmation or delivery update is usually utility. Meta decides the category from the content of your template, so you do not always choose it yourself.
Run the same example. 1,000 marketing messages at about €0.13 = about €130 in Meta fees. On top comes the fee of the platform you send and reply from, which is separate from Meta's rate. Saysimple's lowest plan, Grow (3 users), costs €119 per month on annual billing (€139 per month billed monthly). Sending to many contacts at once uses the Broadcasting add-on at €59 per month, so the platform fee for this kind of mailing is €178 per month on annual billing. The current prices are on the Saysimple pricing page. Check whether fees are quoted with or without VAT. When customers reply, their messages are free for you. If your team answers within 24 hours, service messages above the 1,000 free per phone number per month are charged from 1 October 2026.
Put together for a price list you send every quarter: 4 mailings × about €130 in Meta fees = about €520, plus 12 months × €178 = €2,136 for the platform. That is about €2,656 a year, against €5,600 in stamps alone. The platform also covers your shared inbox for all other customer conversations, so not all of it is a cost of this mailing.
| Per 1,000 contacts | Letter by post | WhatsApp marketing message | WhatsApp utility message |
|---|---|---|---|
| Sending cost | €1,400 in PostNL stamps (1,000 × €1.40) | About €130 in Meta fees (1,000 × about €0.13) | About €41 in Meta fees (1,000 × about €0.04) |
| Printing, envelope, handling time | Fill in your own figures | Not applicable | Not applicable |
| Platform fee | None | €178 per month (Grow plan with 3 users plus the Broadcasting add-on, annual billing) | From €119 per month (Grow plan with 3 users, annual billing) |
| Customer consent | Not required | Opt-in and approved template required | Opt-in and approved template required |
| Signal after sending | None | Sent, delivered, read (if the recipient has read receipts on) | Same statuses |
| Replying | Only via a phone number or QR code you add yourself | The customer answers in the chat | Same |
Measurability: What Do You Know After Sending?
After you post a letter, you know the day you posted it. You do not know whether it arrived, whether anyone opened it or whether the price list went straight in the bin. A QR code or a dedicated phone number on the letter gives you a rough signal, but you have to add it, track it and match it to the customer yourself.
A WhatsApp message comes with statuses. You see whether it was sent, delivered and, when the recipient has read receipts on, read. A missing read status does not prove the message went unread, because some people switch receipts off. Our view: a read tick is not a result, but it is a signal a letter cannot give you at all. The better measure is how many customers reply or order afterwards.
A Channel Where Your Customer Can Reply Right Away
A customer who wants to order from a letter has to pick up the phone, write an email or wait for the next visit. In WhatsApp they answer in the same thread, and your team sees the reply in a shared inbox next to every other conversation.
Datamars UK, a UK supplier of livestock and farming equipment, relied on email, direct mail and in-person events before it started using Saysimple. According to its Datamars UK case study, those channels lacked the immediacy and personalisation modern farmers need. A targeted WhatsApp campaign to 400 people then produced a 300% return on investment (ROI) in sales over one weekend. That is the result of one campaign at one customer, not an average, and the case does not compare cost per contact between post and WhatsApp. How campaigns like that are set up is explained in the ultimate guide to WhatsApp Broadcasting.
When the Letter Still Wins
WhatsApp does not replace all post, and we would not tell a wholesaler to try. The letter is the better choice in these cases:
- Formal or legal notices, where you want a paper trail.
- Customers who have not opted in. WhatsApp marketing needs their consent and an approved template, a letter does not.
- Customers who ask for paper.
- Very low, stable volumes. The platform fee comes on top of Meta's rate, so a handful of letters a month can be cheaper than a platform.
For the last case, do the maths with your own numbers. WhatsApp is cheaper when contacts × Meta rate + platform fee is lower than letters × (your rate per letter + printing + envelope + handling time).
How to Start Without Dropping Your Letters
Our advice for a wholesaler: take one recurring mailing, such as the price list or a promotion, and test the WhatsApp version first. Keep the letter for what has to be formal.
- Pick one mailing you send at least every quarter.
- Collect opt-in: ask when the order is placed, at the trade counter or on your invoice.
- Have the template approved and check which category Meta assigns to it.
- For one quarter, send WhatsApp to customers with opt-in and keep posting letters to the rest. Compare the cost per reply, not only the cost per message.
To send this you need a WhatsApp Business API number via a platform, a list of customers with opt-in and an approved template. A communication setup for wholesalers bundles those in one place.
Closing thoughts
The stamp is a known price, and everything after it is a guess. A WhatsApp message has a lower and more transparent fee per contact, a status you can follow and a reply path that ends in a shared inbox. The letter keeps its place where paper or a formal record is required.
Want to run this for your own volume? Request a Saysimple demo and we will work through one of your existing mailings together.
Sources
- Meta for Developers: Pricing on the WhatsApp Business Platform, for message categories, rates per recipient country and the charges for service messages from 1 October 2026.
- PostNL newsroom: PostNL announces new stamp tariffs effective 12 July 2026, for the standard stamp price of €1.40 for a letter or card up to 20 g.
