diff --git a/backend/README.md b/backend/README.md
index 9d04665..cd3b17a 100644
--- a/backend/README.md
+++ b/backend/README.md
@@ -8,6 +8,7 @@ Setup
 
    cp .env.example .env
    # then edit .env to set DATABASE_URL
+   # and (optional) Postal settings for email sending
 
 2. Install dependencies
 
@@ -27,5 +28,46 @@ API
 - GET /api/bikes - list available bike types
 - POST /api/bookings - create a booking (bike_type, start_date, end_date, name, email)
 - GET /api/bookings - list recent bookings
+- PATCH /api/bookings/:id/status - update booking status (pending | accepted | refused)
+- PATCH /api/bookings/:id - update booking fields
+- DELETE /api/bookings/:id - delete a booking
 
+Email sending (Postal)
 
+When a booking is transitioned to "accepted", the backend attempts to send a confirmation email to the booking's email address(es) using Postal.
+
+Configuration (in .env):
+
+- POSTAL_URL: Base URL of your Postal server (no trailing slash), e.g. https://postal.example.com
+- POSTAL_API_KEY: API key with permission to send messages
+- POSTAL_FROM: From email address used for sending, e.g. no-reply@yourdomain.tld
+- POSTAL_FROM_NAME: Optional display name for the from address (e.g. "AGEP Cargobike")
+- POSTAL_REPLY_TO: Optional reply-to email address
+
+Notes:
+- If Postal variables are not set, the server will skip email sending and log a warning.
+- Multiple recipient emails are supported; separate with commas or semicolons.
+
+Quick test of email sending
+
+1) Create a pending booking (adjust dates and recipient):
+
+   curl -sS -X POST http://localhost:3000/api/bookings \
+     -H 'Content-Type: application/json' \
+     -d '{
+       "bike_types": [1000],
+       "start_date": "2025-10-20",
+       "start_time": "10:00",
+       "end_date": "2025-10-20",
+       "end_time": "12:00",
+       "name": "Association Test",
+       "email": "recipient@example.com"
+     }'
+
+2) Accept the booking (replace <ID> by the returned id); this triggers the Postal email:
+
+   curl -sS -X PATCH http://localhost:3000/api/bookings/<ID>/status \
+     -H 'Content-Type: application/json' \
+     -d '{"status":"accepted"}'
+
+If Postal is configured correctly, a confirmation email will be sent in the background. Check your Postal logs if you need to diagnose delivery.
diff --git a/backend/package-lock.json b/backend/package-lock.json
index 0333ce7..2b3be37 100644
--- a/backend/package-lock.json
+++ b/backend/package-lock.json
@@ -11,6 +11,7 @@
         "cors": "^2.8.5",
         "dotenv": "^16.3.1",
         "express": "^4.18.2",
+        "node-fetch": "^3.3.2",
         "pg": "^8.11.0"
       },
       "devDependencies": {
@@ -237,6 +238,15 @@
         "node": ">= 0.10"
       }
     },
+    "node_modules/data-uri-to-buffer": {
+      "version": "4.0.1",
+      "resolved": "https://registry.npmjs.org/data-uri-to-buffer/-/data-uri-to-buffer-4.0.1.tgz",
+      "integrity": "sha512-0R9ikRb668HB7QDxT1vkpuUBtqc53YyAwMwGeUFKRojY/NWKvdZ+9UYtRfGmhqNbRkTSVpMbmyhXipFFv2cb/A==",
+      "license": "MIT",
+      "engines": {
+        "node": ">= 12"
+      }
+    },
     "node_modules/debug": {
       "version": "2.6.9",
       "resolved": "https://registry.npmjs.org/debug/-/debug-2.6.9.tgz",
@@ -397,6 +407,29 @@
         "url": "https://opencollective.com/express"
       }
     },
+    "node_modules/fetch-blob": {
+      "version": "3.2.0",
+      "resolved": "https://registry.npmjs.org/fetch-blob/-/fetch-blob-3.2.0.tgz",
+      "integrity": "sha512-7yAQpD2UMJzLi1Dqv7qFYnPbaPx7ZfFK6PiIxQ4PfkGPyNyl2Ugx+a/umUonmKqjhM4DnfbMvdX6otXq83soQQ==",
+      "funding": [
+        {
+          "type": "github",
+          "url": "https://github.com/sponsors/jimmywarting"
+        },
+        {
+          "type": "paypal",
+          "url": "https://paypal.me/jimmywarting"
+        }
+      ],
+      "license": "MIT",
+      "dependencies": {
+        "node-domexception": "^1.0.0",
+        "web-streams-polyfill": "^3.0.3"
+      },
+      "engines": {
+        "node": "^12.20 || >= 14.13"
+      }
+    },
     "node_modules/fill-range": {
       "version": "7.1.1",
       "resolved": "https://registry.npmjs.org/fill-range/-/fill-range-7.1.1.tgz",
@@ -428,6 +461,18 @@
         "node": ">= 0.8"
       }
     },
+    "node_modules/formdata-polyfill": {
+      "version": "4.0.10",
+      "resolved": "https://registry.npmjs.org/formdata-polyfill/-/formdata-polyfill-4.0.10.tgz",
+      "integrity": "sha512-buewHzMvYL29jdeQTVILecSaZKnt/RJWjoZCF5OW60Z67/GmSLBkOFM7qh1PI3zFNtJbaZL5eQu1vLfazOwj4g==",
+      "license": "MIT",
+      "dependencies": {
+        "fetch-blob": "^3.1.2"
+      },
+      "engines": {
+        "node": ">=12.20.0"
+      }
+    },
     "node_modules/forwarded": {
       "version": "0.2.0",
       "resolved": "https://registry.npmjs.org/forwarded/-/forwarded-0.2.0.tgz",
@@ -759,6 +804,44 @@
         "node": ">= 0.6"
       }
     },
+    "node_modules/node-domexception": {
+      "version": "1.0.0",
+      "resolved": "https://registry.npmjs.org/node-domexception/-/node-domexception-1.0.0.tgz",
+      "integrity": "sha512-/jKZoMpw0F8GRwl4/eLROPA3cfcXtLApP0QzLmUT/HuPCZWyB7IY9ZrMeKw2O/nFIqPQB3PVM9aYm0F312AXDQ==",
+      "deprecated": "Use your platform's native DOMException instead",
+      "funding": [
+        {
+          "type": "github",
+          "url": "https://github.com/sponsors/jimmywarting"
+        },
+        {
+          "type": "github",
+          "url": "https://paypal.me/jimmywarting"
+        }
+      ],
+      "license": "MIT",
+      "engines": {
+        "node": ">=10.5.0"
+      }
+    },
+    "node_modules/node-fetch": {
+      "version": "3.3.2",
+      "resolved": "https://registry.npmjs.org/node-fetch/-/node-fetch-3.3.2.tgz",
+      "integrity": "sha512-dRB78srN/l6gqWulah9SrxeYnxeddIG30+GOqK/9OlLVyLg3HPnr6SqOWTWOXKRwC2eGYCkZ59NNuSgvSrpgOA==",
+      "license": "MIT",
+      "dependencies": {
+        "data-uri-to-buffer": "^4.0.0",
+        "fetch-blob": "^3.1.4",
+        "formdata-polyfill": "^4.0.10"
+      },
+      "engines": {
+        "node": "^12.20.0 || ^14.13.1 || >=16.0.0"
+      },
+      "funding": {
+        "type": "opencollective",
+        "url": "https://opencollective.com/node-fetch"
+      }
+    },
     "node_modules/nodemon": {
       "version": "3.1.10",
       "resolved": "https://registry.npmjs.org/nodemon/-/nodemon-3.1.10.tgz",
@@ -1379,6 +1462,15 @@
         "node": ">= 0.8"
       }
     },
+    "node_modules/web-streams-polyfill": {
+      "version": "3.3.3",
+      "resolved": "https://registry.npmjs.org/web-streams-polyfill/-/web-streams-polyfill-3.3.3.tgz",
+      "integrity": "sha512-d2JWLCivmZYTSIoge9MsgFCZrt571BikcWGYkjC1khllbTeDlGqZ2D8vD8E/lJa8WGWbb7Plm8/XJYV7IJHZZw==",
+      "license": "MIT",
+      "engines": {
+        "node": ">= 8"
+      }
+    },
     "node_modules/xtend": {
       "version": "4.0.2",
       "resolved": "https://registry.npmjs.org/xtend/-/xtend-4.0.2.tgz",
diff --git a/backend/package.json b/backend/package.json
index e51ea88..9e7546a 100644
--- a/backend/package.json
+++ b/backend/package.json
@@ -11,10 +11,10 @@
     "cors": "^2.8.5",
     "dotenv": "^16.3.1",
     "express": "^4.18.2",
-    "pg": "^8.11.0"
+    "pg": "^8.11.0",
+    "node-fetch": "^3.3.2"
   },
   "devDependencies": {
     "nodemon": "^3.0.1"
   }
 }
-
diff --git a/backend/postal.js b/backend/postal.js
new file mode 100644
index 0000000..730d5e9
--- /dev/null
+++ b/backend/postal.js
@@ -0,0 +1,80 @@
+// Lightweight Postal API client
+// Sends messages via Postal /api/v1/send/message
+// Requires env: POSTAL_URL, POSTAL_API_KEY, POSTAL_FROM, optional POSTAL_FROM_NAME, POSTAL_REPLY_TO
+
+import dotenv from 'dotenv'
+dotenv.config()
+
+let _fetch = null
+
+async function getFetch() {
+  if (typeof globalThis.fetch === 'function') return globalThis.fetch
+  if (_fetch) return _fetch
+  try {
+    const mod = await import('node-fetch')
+    _fetch = mod.default
+    return _fetch
+  } catch (e) {
+    throw new Error('fetch is not available and node-fetch is not installed. Please install node-fetch or use Node 18+.')
+  }
+}
+
+function ensureArray(v) {
+  if (!v) return []
+  if (Array.isArray(v)) return v
+  if (typeof v === 'string') return v.split(/[;,]/).map(s => s.trim()).filter(Boolean)
+  return [String(v)]
+}
+
+function fmtFromAddress(email, name) {
+  const e = String(email || '').trim()
+  const n = String(name || '').trim()
+  if (!e) return ''
+  return n ? `${n} <${e}>` : e
+}
+
+export async function sendPostalEmail({ to, subject, text, html, cc = [], bcc = [] }) {
+  const base = (process.env.POSTAL_URL || '').replace(/\/$/, '')
+  const apiKey = process.env.POSTAL_API_KEY || ''
+  const fromEmail = process.env.POSTAL_FROM || ''
+  const fromName = process.env.POSTAL_FROM_NAME || ''
+  const replyTo = process.env.POSTAL_REPLY_TO || ''
+
+  if (!base || !apiKey || !fromEmail) {
+    throw new Error('Postal configuration missing: POSTAL_URL, POSTAL_API_KEY, POSTAL_FROM are required')
+  }
+
+  const endpoint = `${base}/api/v1/send/message`
+  const payload = {
+    api_key: apiKey,
+    from: fmtFromAddress(fromEmail, fromName),
+    to: ensureArray(to),
+    subject: subject || '',
+    html_body: html || undefined,
+    plain_body: text || undefined,
+  }
+  const ccArr = ensureArray(cc)
+  const bccArr = ensureArray(bcc)
+  if (ccArr.length) payload.cc = ccArr
+  if (bccArr.length) payload.bcc = bccArr
+  if (replyTo) payload.reply_to = replyTo
+
+  const fetchImpl = await getFetch()
+  const res = await fetchImpl(endpoint, {
+    method: 'POST',
+    headers: { 'Content-Type': 'application/json' },
+    body: JSON.stringify(payload),
+  })
+
+  let data
+  try {
+    data = await res.json()
+  } catch (e) {
+    throw new Error(`Postal response parse error: HTTP ${res.status}`)
+  }
+  if (!res.ok || data?.status !== 'success') {
+    const errMsg = data?.data?.message || data?.message || JSON.stringify(data)
+    throw new Error(`Postal send failed: ${errMsg}`)
+  }
+  return data
+}
diff --git a/backend/server.js b/backend/server.js
index 0e76df0..8880cb1 100644
--- a/backend/server.js
+++ b/backend/server.js
@@ -2,6 +2,7 @@ import express from 'express'
 import cors from 'cors'
 import dotenv from 'dotenv'
 import { pool } from './db.js'
+import { sendPostalEmail } from './postal.js'
 
 dotenv.config()
 
@@ -120,23 +121,118 @@ app.patch('/api/bookings/:id/status', async (req, res) => {
     if (!allowed.includes(status)) return res.status(400).json({ error: 'Invalid status' })
 
     // Read current status to enforce immutability once accepted
-    const current = await pool.query('SELECT status FROM bookings WHERE id = $1', [id])
+    const current = await pool.query('SELECT * FROM bookings WHERE id = $1', [id])
     if (current.rowCount === 0) return res.status(404).json({ error: 'Booking not found' })
-    const curr = current.rows[0].status
-    if (curr === 'accepted' && status !== 'accepted') {
+    const prev = current.rows[0]
+    const currStatus = prev.status
+    if (currStatus === 'accepted' && status !== 'accepted') {
       return res.status(400).json({ error: 'Accepted bookings cannot change status' })
     }
 
     const result = await pool.query('UPDATE bookings SET status = $1 WHERE id = $2 RETURNING *', [status, id])
     if (result.rowCount === 0) return res.status(404).json({ error: 'Booking not found' })
 
-    res.json({ booking: sanitizeBooking(result.rows[0]) })
+    const updated = result.rows[0]
+    // Respond immediately
+    res.json({ booking: sanitizeBooking(updated) })
+
+    // Fire-and-forget: if newly accepted, send confirmation email (do not block response)
+    if (status === 'accepted' && currStatus !== 'accepted') {
+      try {
+        await sendAcceptanceEmail(updated)
+      } catch (e) {
+        console.warn(`Postal email send failed for booking #${id}:`, e?.message || e)
+      }
+    }
   } catch (err) {
     console.error(err)
     res.status(500).json({ error: 'Server error' })
   }
 })
 
+// Compose and send acceptance email via Postal
+async function sendAcceptanceEmail(bookingRow) {
+  const postalEnabled = process.env.POSTAL_URL && process.env.POSTAL_API_KEY && process.env.POSTAL_FROM
+  if (!postalEnabled) {
+    console.warn('Postal not configured (POSTAL_URL/POSTAL_API_KEY/POSTAL_FROM). Skipping email send.')
+    return
+  }
+
+  const b = sanitizeBooking(bookingRow)
+  // recipients: allow comma or semicolon separated values
+  const recipients = String(b.email || '')
+    .split(/[;,]/)
+    .map(s => s.trim())
+    .filter(s => s.length > 0)
+
+  if (recipients.length === 0) {
+    console.warn(`Booking #${b.id} has no recipient email; skipping send.`)
+    return
+  }
+
+  // bikes list from single or multi
+  const bikeList = (() => {
+    const parts = []
+    if (Number.isFinite(b.bike_type)) parts.push(String(b.bike_type))
+    if (typeof b.bike_types === 'string' && b.bike_types.trim()) {
+      parts.push(...b.bike_types.split(',').map(s => s.trim()).filter(Boolean))
+    }
+    return parts.join(', ')
+  })()
+
+  const rangeLabel = (() => {
+    const sDate = b.start_date
+    const eDate = b.end_date
+    const st = (b.start_time && b.start_time.length) ? b.start_time : '00:00'
+    const et = (b.end_time && b.end_time.length) ? b.end_time : '23:59'
+    if (sDate && eDate && sDate === eDate) return `${toFR(sDate)} ${st} → ${et}`
+    return `${toFR(sDate)} ${st} → ${toFR(eDate)} ${et}`
+  })()
+
+  const subject = 'AGEP – Confirmation de réservation de cargobike'
+  const greeting = b.name ? `Bonjour ${b.name},` : 'Bonjour,'
+  const text = `${greeting}
+
+Votre réservation de cargobike a été validée.
+
+Détails de la réservation:
+- Période: ${rangeLabel}
+- Cargobike(s): ${bikeList || '—'}
+
+Vous recevrez prochainement des informations complémentaires si nécessaire.
+
+Cordialement,
+Association AGEP`
+
+  const html = `
+  <p>${escapeHtml(greeting)}</p>
+  <p>Votre réservation de cargobike a été <strong>validée</strong>.</p>
+  <p><strong>Détails de la réservation</strong><br/>
+    • Période: ${escapeHtml(rangeLabel)}<br/>
+    • Cargobike(s): ${escapeHtml(bikeList || '—')}
+  </p>
+  <p>Vous recevrez prochainement des informations complémentaires si nécessaire.</p>
+  <p>Cordialement,<br/>Association AGEP</p>
+  `
+
+  await sendPostalEmail({
+    to: recipients,
+    subject,
+    text,
+    html,
+  })
+}
+
+function toFR(iso) {
+  if (!iso) return ''
+  const m = /^(\d{4})-(\d{2})-(\d{2})$/.exec(String(iso))
+  if (!m) return String(iso)
+  return `${m[3]}/${m[2]}/${m[1]}`
+}
+function escapeHtml(s) {
+  return String(s).replaceAll('&','&amp;').replaceAll('<','&lt;').replaceAll('>','&gt;')
+}
+
 // Update booking fields (non-status)
 app.patch('/api/bookings/:id', async (req, res) => {
   try {