diff --git a/tests/js/app.test.js b/tests/js/app.test.js
index 5456a9b..2e9d647 100644
--- a/tests/js/app.test.js
+++ b/tests/js/app.test.js
@@ -2008,6 +2008,71 @@ describe('app.js DOMContentLoaded', () => {
             expect(serviceSelect.value).toBe('5')
         })
 
+        it('prefill with serviceId fetch error covers catch branch', async () => {
+            globalThis.fetch = vi.fn(() => Promise.reject(new Error('Network error')))
+
+            const initialLines = JSON.stringify([
+                { pos: 0, title: 'Fail line', description: '', priceHt: '10.00', type: 'esymail', serviceId: 99 }
+            ])
+            document.body.innerHTML = `
+                <div id="lines-container" data-initial-lines='${initialLines}'></div>
+                <button id="add-line-btn">Ajouter</button>
+                <script id="line-template" type="text/html">${lineTemplate}<\/script>
+                <div id="total-ht">0.00 EUR</div>
+                <form id="devis-form"></form>
+            `
+            await loadApp()
+            await new Promise(r => setTimeout(r, 200))
+
+            const container = document.getElementById('lines-container')
+            const row = container.querySelector('.line-row')
+            expect(row).not.toBeNull()
+            // Service select should remain disabled since fetch failed
+            const serviceSelect = row.querySelector('.line-service-id')
+            expect(serviceSelect.disabled).toBe(true)
+        })
+
+        it('prefill with missing optional fields uses defaults', async () => {
+            const initialLines = JSON.stringify([
+                { pos: 0 }
+            ])
+            document.body.innerHTML = `
+                <div id="lines-container" data-initial-lines='${initialLines}'></div>
+                <button id="add-line-btn">Ajouter</button>
+                <script id="line-template" type="text/html">${lineTemplate}<\/script>
+                <div id="total-ht">0.00 EUR</div>
+                <form id="devis-form"></form>
+            `
+            await loadApp()
+
+            const container = document.getElementById('lines-container')
+            const row = container.querySelector('.line-row')
+            expect(row).not.toBeNull()
+            expect(row.querySelector('input[name$="[title]"]').value).toBe('')
+            expect(row.querySelector('textarea[name$="[description]"]').value).toBe('')
+            expect(row.querySelector('.line-price').value).toBe('0.00')
+        })
+
+        it('prefill with type but no serviceId does not fetch', async () => {
+            globalThis.fetch = vi.fn()
+
+            const initialLines = JSON.stringify([
+                { pos: 0, title: 'Host', priceHt: '50.00', type: 'hosting' }
+            ])
+            document.body.innerHTML = `
+                <div id="lines-container" data-initial-lines='${initialLines}'></div>
+                <button id="add-line-btn">Ajouter</button>
+                <script id="line-template" type="text/html">${lineTemplate}<\/script>
+                <div id="total-ht">0.00 EUR</div>
+                <form id="devis-form"></form>
+            `
+            await loadApp()
+            await new Promise(r => setTimeout(r, 200))
+
+            // hosting type with no serviceId should not trigger fetch
+            expect(globalThis.fetch).not.toHaveBeenCalled()
+        })
+
         it('prefill with invalid JSON catches the error silently', async () => {
             document.body.innerHTML = `
                 <div id="lines-container" data-initial-lines='{{invalid json'></div>
diff --git a/tests/js/entreprise-search.test.js b/tests/js/entreprise-search.test.js
new file mode 100644
index 0000000..5bf6282
--- /dev/null
+++ b/tests/js/entreprise-search.test.js
@@ -0,0 +1,391 @@
+import { describe, it, expect, beforeEach, vi } from 'vitest'
+import { initEntrepriseSearch } from '../../assets/modules/entreprise-search.js'
+
+describe('entreprise-search.js', () => {
+    beforeEach(() => {
+        document.body.innerHTML = ''
+        vi.restoreAllMocks()
+    })
+
+    it('does nothing without modal or openBtn', () => {
+        document.body.innerHTML = '<div></div>'
+        initEntrepriseSearch()
+        expect(true).toBe(true)
+    })
+
+    it('opens modal on openBtn click', () => {
+        document.body.innerHTML = `
+            <div id="modal-entreprise" class="hidden"></div>
+            <div id="modal-overlay"></div>
+            <button id="modal-close"></button>
+            <button id="btn-search-entreprise"></button>
+            <input id="search-entreprise-input">
+            <button id="search-entreprise-btn"></button>
+            <div id="search-entreprise-results"></div>
+            <div id="search-entreprise-status" class="hidden"></div>
+        `
+        initEntrepriseSearch()
+        document.getElementById('btn-search-entreprise').click()
+        expect(document.getElementById('modal-entreprise').classList.contains('hidden')).toBe(false)
+    })
+
+    it('closes modal on closeBtn click', () => {
+        document.body.innerHTML = `
+            <div id="modal-entreprise"></div>
+            <div id="modal-overlay"></div>
+            <button id="modal-close"></button>
+            <button id="btn-search-entreprise"></button>
+            <input id="search-entreprise-input">
+            <button id="search-entreprise-btn"></button>
+            <div id="search-entreprise-results"></div>
+            <div id="search-entreprise-status" class="hidden"></div>
+        `
+        initEntrepriseSearch()
+        document.getElementById('modal-close').click()
+        expect(document.getElementById('modal-entreprise').classList.contains('hidden')).toBe(true)
+    })
+
+    it('closes modal on overlay click', () => {
+        document.body.innerHTML = `
+            <div id="modal-entreprise"></div>
+            <div id="modal-overlay"></div>
+            <button id="modal-close"></button>
+            <button id="btn-search-entreprise"></button>
+            <input id="search-entreprise-input">
+            <button id="search-entreprise-btn"></button>
+            <div id="search-entreprise-results"></div>
+            <div id="search-entreprise-status" class="hidden"></div>
+        `
+        initEntrepriseSearch()
+        document.getElementById('modal-overlay').click()
+        expect(document.getElementById('modal-entreprise').classList.contains('hidden')).toBe(true)
+    })
+
+    it('closes modal on Escape key', () => {
+        document.body.innerHTML = `
+            <div id="modal-entreprise"></div>
+            <div id="modal-overlay"></div>
+            <button id="modal-close"></button>
+            <button id="btn-search-entreprise"></button>
+            <input id="search-entreprise-input">
+            <button id="search-entreprise-btn"></button>
+            <div id="search-entreprise-results"></div>
+            <div id="search-entreprise-status" class="hidden"></div>
+        `
+        initEntrepriseSearch()
+        document.dispatchEvent(new KeyboardEvent('keydown', { key: 'Escape' }))
+        expect(document.getElementById('modal-entreprise').classList.contains('hidden')).toBe(true)
+    })
+
+    it('does not search when query is too short', async () => {
+        document.body.innerHTML = `
+            <div id="modal-entreprise"></div>
+            <div id="modal-overlay"></div>
+            <button id="modal-close"></button>
+            <button id="btn-search-entreprise"></button>
+            <input id="search-entreprise-input" value="a">
+            <button id="search-entreprise-btn"></button>
+            <div id="search-entreprise-results"></div>
+            <div id="search-entreprise-status" class="hidden"></div>
+        `
+        globalThis.fetch = vi.fn()
+        initEntrepriseSearch()
+        document.getElementById('search-entreprise-btn').click()
+        await new Promise(r => setTimeout(r, 100))
+        expect(globalThis.fetch).not.toHaveBeenCalled()
+    })
+
+    it('shows no results message', async () => {
+        document.body.innerHTML = `
+            <div id="modal-entreprise"></div>
+            <div id="modal-overlay"></div>
+            <button id="modal-close"></button>
+            <button id="btn-search-entreprise"></button>
+            <input id="search-entreprise-input" value="zzzzz">
+            <button id="search-entreprise-btn"></button>
+            <div id="search-entreprise-results"></div>
+            <div id="search-entreprise-status" class="hidden"></div>
+        `
+        globalThis.fetch = vi.fn(() => Promise.resolve({ json: () => Promise.resolve({ results: [], total_results: 0 }) }))
+        initEntrepriseSearch()
+        document.getElementById('search-entreprise-btn').click()
+        await new Promise(r => setTimeout(r, 100))
+        expect(document.getElementById('search-entreprise-status').textContent).toContain('Aucun resultat')
+    })
+
+    it('shows results and fills form on click', async () => {
+        document.body.innerHTML = `
+            <div id="modal-entreprise"></div>
+            <div id="modal-overlay"></div>
+            <button id="modal-close"></button>
+            <button id="btn-search-entreprise"></button>
+            <input id="search-entreprise-input" value="acme">
+            <button id="search-entreprise-btn"></button>
+            <div id="search-entreprise-results"></div>
+            <div id="search-entreprise-status" class="hidden"></div>
+            <input id="raisonSociale">
+            <input id="siret">
+            <input id="rcs">
+            <input id="numTva">
+            <input id="ape">
+            <input id="address">
+            <input id="zipCode">
+            <input id="city">
+            <input id="geoLat">
+            <input id="geoLong">
+            <input id="typeCompany">
+            <input id="rna">
+            <input id="firstName">
+            <input id="lastName">
+        `
+        globalThis.fetch = vi.fn(() => Promise.resolve({
+            json: () => Promise.resolve({
+                results: [{
+                    nom_raison_sociale: 'ACME SA',
+                    nom_complet: 'ACME SA COMPLETE',
+                    siren: '123456789',
+                    etat_administratif: 'A',
+                    activite_principale: '6201Z',
+                    nature_juridique: '5710',
+                    siege: {
+                        siret: '12345678901234',
+                        numero_voie: '42',
+                        type_voie: 'rue',
+                        libelle_voie: 'de la Paix',
+                        code_postal: '75001',
+                        libelle_commune: 'Paris',
+                        geo_adresse: '42 rue de la Paix 75001 Paris',
+                        latitude: '48.8',
+                        longitude: '2.3',
+                    },
+                    dirigeants: [{ nom: 'DUPONT', prenoms: 'Jean Pierre' }],
+                    complements: { identifiant_association: '' },
+                }],
+                total_results: 1,
+            })
+        }))
+        initEntrepriseSearch()
+        document.getElementById('search-entreprise-btn').click()
+        await new Promise(r => setTimeout(r, 100))
+
+        const status = document.getElementById('search-entreprise-status')
+        expect(status.textContent).toContain('1 resultat(s)')
+
+        const results = document.getElementById('search-entreprise-results')
+        expect(results.innerHTML).toContain('ACME SA')
+        expect(results.innerHTML).toContain('Actif')
+
+        // Click to fill form
+        results.querySelector('div').click()
+        expect(document.getElementById('raisonSociale').value).toBe('ACME SA')
+        expect(document.getElementById('siret').value).toBe('12345678901234')
+        expect(document.getElementById('numTva').value).toContain('FR')
+        expect(document.getElementById('ape').value).toBe('6201Z')
+        expect(document.getElementById('address').value).toBe('42 rue de la Paix')
+        expect(document.getElementById('zipCode').value).toBe('75001')
+        expect(document.getElementById('city').value).toBe('Paris')
+        expect(document.getElementById('typeCompany').value).toBe('sas')
+        expect(document.getElementById('firstName').value).toBe('Jean')
+        expect(document.getElementById('lastName').value).toBe('Dupont')
+    })
+
+    it('handles association type with RNA', async () => {
+        document.body.innerHTML = `
+            <div id="modal-entreprise"></div>
+            <div id="modal-overlay"></div>
+            <button id="modal-close"></button>
+            <button id="btn-search-entreprise"></button>
+            <input id="search-entreprise-input" value="asso">
+            <button id="search-entreprise-btn"></button>
+            <div id="search-entreprise-results"></div>
+            <div id="search-entreprise-status" class="hidden"></div>
+            <input id="raisonSociale">
+            <input id="typeCompany">
+            <input id="rna">
+        `
+        globalThis.fetch = vi.fn(() => Promise.resolve({
+            json: () => Promise.resolve({
+                results: [{
+                    nom_complet: 'Asso Test',
+                    siren: '999888777',
+                    etat_administratif: 'C',
+                    nature_juridique: '9220',
+                    siege: {},
+                    complements: { identifiant_association: 'W123456789' },
+                }],
+                total_results: 1,
+            })
+        }))
+        initEntrepriseSearch()
+        document.getElementById('search-entreprise-btn').click()
+        await new Promise(r => setTimeout(r, 100))
+
+        const results = document.getElementById('search-entreprise-results')
+        expect(results.innerHTML).toContain('Association')
+        expect(results.innerHTML).toContain('Ferme')
+        expect(results.innerHTML).toContain('W123456789')
+
+        results.querySelector('div').click()
+        expect(document.getElementById('rna').value).toBe('W123456789')
+        expect(document.getElementById('typeCompany').value).toBe('association')
+    })
+
+    it('handles fetch error', async () => {
+        document.body.innerHTML = `
+            <div id="modal-entreprise"></div>
+            <div id="modal-overlay"></div>
+            <button id="modal-close"></button>
+            <button id="btn-search-entreprise"></button>
+            <input id="search-entreprise-input" value="fail">
+            <button id="search-entreprise-btn"></button>
+            <div id="search-entreprise-results"></div>
+            <div id="search-entreprise-status" class="hidden"></div>
+        `
+        globalThis.fetch = vi.fn(() => Promise.reject(new Error('Network fail')))
+        initEntrepriseSearch()
+        document.getElementById('search-entreprise-btn').click()
+        await new Promise(r => setTimeout(r, 100))
+        expect(document.getElementById('search-entreprise-status').textContent).toContain('Erreur')
+    })
+
+    it('Enter key triggers search', async () => {
+        document.body.innerHTML = `
+            <div id="modal-entreprise"></div>
+            <div id="modal-overlay"></div>
+            <button id="modal-close"></button>
+            <button id="btn-search-entreprise"></button>
+            <input id="search-entreprise-input" value="test">
+            <button id="search-entreprise-btn"></button>
+            <div id="search-entreprise-results"></div>
+            <div id="search-entreprise-status" class="hidden"></div>
+        `
+        globalThis.fetch = vi.fn(() => Promise.resolve({ json: () => Promise.resolve({ results: [], total_results: 0 }) }))
+        initEntrepriseSearch()
+        document.getElementById('search-entreprise-input').dispatchEvent(new KeyboardEvent('keydown', { key: 'Enter', bubbles: true, cancelable: true }))
+        await new Promise(r => setTimeout(r, 100))
+        expect(globalThis.fetch).toHaveBeenCalled()
+    })
+
+    it('covers resolveTypeCompany branches', async () => {
+        document.body.innerHTML = `
+            <div id="modal-entreprise"></div>
+            <div id="modal-overlay"></div>
+            <button id="modal-close"></button>
+            <button id="btn-search-entreprise"></button>
+            <input id="search-entreprise-input" value="multi">
+            <button id="search-entreprise-btn"></button>
+            <div id="search-entreprise-results"></div>
+            <div id="search-entreprise-status" class="hidden"></div>
+            <input id="typeCompany">
+        `
+        const types = [
+            { code: '1000', expected: 'auto-entrepreneur' },
+            { code: '5400', expected: 'sarl' },
+            { code: '5599', expected: 'sarl' }, // 55xx matches sarl before sa check
+            { code: '5200', expected: 'eurl' },
+            { code: '6500', expected: 'sci' },
+            { code: '9999', expected: '' },
+        ]
+
+        for (const { code, expected } of types) {
+            globalThis.fetch = vi.fn(() => Promise.resolve({
+                json: () => Promise.resolve({
+                    results: [{ nom_complet: 'Test', siren: '111', nature_juridique: code, siege: {} }],
+                    total_results: 1,
+                })
+            }))
+            initEntrepriseSearch()
+            document.getElementById('search-entreprise-btn').click()
+            await new Promise(r => setTimeout(r, 100))
+
+            const results = document.getElementById('search-entreprise-results')
+            results.querySelector('div').click()
+
+            const typeVal = document.getElementById('typeCompany').value
+            if (expected) {
+                expect(typeVal).toBe(expected)
+            }
+            document.getElementById('typeCompany').value = ''
+        }
+    })
+
+    it('fillFieldIfEmpty does not overwrite existing value', async () => {
+        document.body.innerHTML = `
+            <div id="modal-entreprise"></div>
+            <div id="modal-overlay"></div>
+            <button id="modal-close"></button>
+            <button id="btn-search-entreprise"></button>
+            <input id="search-entreprise-input" value="pre">
+            <button id="search-entreprise-btn"></button>
+            <div id="search-entreprise-results"></div>
+            <div id="search-entreprise-status" class="hidden"></div>
+            <input id="firstName" value="Existing">
+            <input id="lastName">
+        `
+        globalThis.fetch = vi.fn(() => Promise.resolve({
+            json: () => Promise.resolve({
+                results: [{ nom_complet: 'Test', siren: '111', siege: {}, dirigeants: [{ nom: 'NEW', prenoms: 'Name' }] }],
+                total_results: 1,
+            })
+        }))
+        initEntrepriseSearch()
+        document.getElementById('search-entreprise-btn').click()
+        await new Promise(r => setTimeout(r, 100))
+
+        document.getElementById('search-entreprise-results').querySelector('div').click()
+        expect(document.getElementById('firstName').value).toBe('Existing')
+        expect(document.getElementById('lastName').value).toBe('New')
+    })
+
+    it('computeTva returns empty for falsy siren', async () => {
+        document.body.innerHTML = `
+            <div id="modal-entreprise"></div>
+            <div id="modal-overlay"></div>
+            <button id="modal-close"></button>
+            <button id="btn-search-entreprise"></button>
+            <input id="search-entreprise-input" value="no-siren">
+            <button id="search-entreprise-btn"></button>
+            <div id="search-entreprise-results"></div>
+            <div id="search-entreprise-status" class="hidden"></div>
+            <input id="numTva">
+        `
+        globalThis.fetch = vi.fn(() => Promise.resolve({
+            json: () => Promise.resolve({
+                results: [{ nom_complet: 'No Siren', siege: {} }],
+                total_results: 1,
+            })
+        }))
+        initEntrepriseSearch()
+        document.getElementById('search-entreprise-btn').click()
+        await new Promise(r => setTimeout(r, 100))
+
+        document.getElementById('search-entreprise-results').querySelector('div').click()
+        expect(document.getElementById('numTva').value).toBe('')
+    })
+
+    it('buildRcs returns empty when no siren or city', async () => {
+        document.body.innerHTML = `
+            <div id="modal-entreprise"></div>
+            <div id="modal-overlay"></div>
+            <button id="modal-close"></button>
+            <button id="btn-search-entreprise"></button>
+            <input id="search-entreprise-input" value="norcs">
+            <button id="search-entreprise-btn"></button>
+            <div id="search-entreprise-results"></div>
+            <div id="search-entreprise-status" class="hidden"></div>
+            <input id="rcs">
+        `
+        globalThis.fetch = vi.fn(() => Promise.resolve({
+            json: () => Promise.resolve({
+                results: [{ nom_complet: 'No RCS', siege: {} }],
+                total_results: 1,
+            })
+        }))
+        initEntrepriseSearch()
+        document.getElementById('search-entreprise-btn').click()
+        await new Promise(r => setTimeout(r, 100))
+
+        document.getElementById('search-entreprise-results').querySelector('div').click()
+        expect(document.getElementById('rcs').value).toBe('')
+    })
+})