diff --git a/src/app/api/v1/documents/[id]/remind/route.ts b/src/app/api/v1/documents/[id]/remind/route.ts
index 35a3d4f..81549eb 100644
--- a/src/app/api/v1/documents/[id]/remind/route.ts
+++ b/src/app/api/v1/documents/[id]/remind/route.ts
@@ -1,14 +1,30 @@
 import { NextResponse } from 'next/server';
+import { z } from 'zod';
 
 import { withAuth, withPermission } from '@/lib/api/helpers';
 import { errorResponse } from '@/lib/errors';
 import { sendReminderIfAllowed } from '@/lib/services/document-reminders';
 
+const remindBodySchema = z
+  .object({
+    signerId: z.string().optional(),
+  })
+  .optional();
+
 export const POST = withAuth(
   withPermission('documents', 'edit', async (req, ctx, params) => {
     try {
-      const sent = await sendReminderIfAllowed(params.id!, ctx.portId);
-      return NextResponse.json({ data: { sent } });
+      let signerId: string | undefined;
+      const text = await req.text();
+      if (text) {
+        const parsed = remindBodySchema.safeParse(JSON.parse(text));
+        if (parsed.success && parsed.data) signerId = parsed.data.signerId;
+      }
+      const result = await sendReminderIfAllowed(params.id!, ctx.portId, {
+        auto: false,
+        signerId,
+      });
+      return NextResponse.json({ data: result });
     } catch (error) {
       return errorResponse(error);
     }
diff --git a/src/lib/services/document-reminders.ts b/src/lib/services/document-reminders.ts
index f563752..328d1b5 100644
--- a/src/lib/services/document-reminders.ts
+++ b/src/lib/services/document-reminders.ts
@@ -1,13 +1,17 @@
-import { and, eq, inArray } from 'drizzle-orm';
+import { and, eq, inArray, isNotNull, sql } from 'drizzle-orm';
 
 import { db } from '@/lib/db';
-import { documents, documentSigners, documentEvents } from '@/lib/db/schema/documents';
-import { interests } from '@/lib/db/schema/interests';
+import {
+  documents,
+  documentSigners,
+  documentEvents,
+  documentTemplates,
+} from '@/lib/db/schema/documents';
 import { ports } from '@/lib/db/schema/ports';
 import { sendReminder as documensoRemind } from '@/lib/services/documenso-client';
 import { logger } from '@/lib/logger';
 
-// BR-023: Reminders only during 9-16 in port timezone, with 24h cooldown
+// ─── Helpers ─────────────────────────────────────────────────────────────────
 
 function getCurrentHourInTimezone(timezone: string): number {
   const now = new Date();
@@ -19,105 +23,189 @@ function getCurrentHourInTimezone(timezone: string): number {
   return parseInt(formatter.format(now), 10);
 }
 
+interface ReminderEligibilityArgs {
+  status: string;
+  documensoId: string | null;
+  remindersDisabled: boolean;
+  reminderCadenceOverride: number | null;
+  templateCadenceDays: number | null;
+  lastReminderAt: Date | null;
+  now?: Date;
+}
+
+/**
+ * Pure cadence/disable check used by the cron path. Auto-mode reminders
+ * additionally enforce the 9–16 port-timezone window, which lives in the
+ * caller below.
+ */
+export function isReminderDue(args: ReminderEligibilityArgs): boolean {
+  const now = args.now ?? new Date();
+  if (!['sent', 'partially_signed'].includes(args.status)) return false;
+  if (args.documensoId == null) return false;
+  if (args.remindersDisabled) return false;
+
+  const cadence = args.reminderCadenceOverride ?? args.templateCadenceDays;
+  if (cadence === null) return false;
+
+  if (args.lastReminderAt == null) return true;
+  const elapsedMs = now.getTime() - args.lastReminderAt.getTime();
+  return elapsedMs >= cadence * 24 * 60 * 60 * 1000;
+}
+
+// ─── sendReminderIfAllowed ───────────────────────────────────────────────────
+
+export interface SendReminderOptions {
+  /** true = cron auto-fire, enforces 9-16 window + cadence cooldown.
+   *  false (default) = manual UI action, bypasses both. */
+  auto?: boolean;
+  /** Optional — target a specific pending signer (parallel mode), or
+   *  bypass the lowest-pending default in sequential mode (must still be the
+   *  next pending signer in that case). */
+  signerId?: string;
+}
+
+export interface SendReminderResult {
+  sent: boolean;
+  reason?: string;
+  signerId?: string;
+}
+
 export async function sendReminderIfAllowed(
   documentId: string,
   portId: string,
-): Promise<boolean> {
+  options: SendReminderOptions = {},
+): Promise<SendReminderResult> {
+  const { auto = false, signerId } = options;
+
   const doc = await db.query.documents.findFirst({
     where: and(eq(documents.id, documentId), eq(documents.portId, portId)),
   });
 
-  if (!doc || !doc.interestId || !doc.documensoId) return false;
-  if (!['sent', 'partially_signed'].includes(doc.status)) return false;
-
-  // Check interest.reminderEnabled
-  const interest = await db.query.interests.findFirst({
-    where: eq(interests.id, doc.interestId),
-  });
-
-  if (!interest?.reminderEnabled) return false;
-
-  // Check port timezone
-  const port = await db.query.ports.findFirst({
-    where: eq(ports.id, portId),
-  });
-
-  const timezone = port?.timezone ?? 'UTC';
-  const currentHour = getCurrentHourInTimezone(timezone);
-
-  if (currentHour < 9 || currentHour >= 16) return false;
-
-  // Check 24h cooldown — last reminder_sent event for this document
-  const twentyFourHoursAgo = new Date(Date.now() - 24 * 60 * 60 * 1000);
-
-  const lastReminder = await db.query.documentEvents.findFirst({
-    where: and(
-      eq(documentEvents.documentId, documentId),
-      eq(documentEvents.eventType, 'reminder_sent'),
-    ),
-    orderBy: (de, { desc }) => [desc(de.createdAt)],
-  });
-
-  if (lastReminder && lastReminder.createdAt > twentyFourHoursAgo) {
-    return false;
+  if (!doc) return { sent: false, reason: 'Document not found' };
+  if (!doc.documensoId) return { sent: false, reason: 'Document has no Documenso id' };
+  if (!['sent', 'partially_signed'].includes(doc.status)) {
+    return { sent: false, reason: `Document is ${doc.status}` };
+  }
+  if (doc.remindersDisabled) {
+    return { sent: false, reason: 'Reminders disabled for this document' };
   }
 
-  // Find current pending signer (lowest signingOrder with status='pending')
-  const pendingSigner = await db.query.documentSigners.findFirst({
-    where: and(
-      eq(documentSigners.documentId, documentId),
-      eq(documentSigners.status, 'pending'),
-    ),
-    orderBy: (ds, { asc }) => [asc(ds.signingOrder)],
-  });
+  // Resolve effective cadence (override → template → null/disabled)
+  let templateCadenceDays: number | null = null;
+  if (auto) {
+    // Auto path needs a cadence to fire at all; manual sends bypass cadence.
+    // We still load the template cadence so `isReminderDue` has the input.
+    const templateRow = doc.fileId
+      ? await db.query.documentTemplates.findFirst({
+          // Fallback: look up by document type if no explicit template_id.
+          where: and(
+            eq(documentTemplates.portId, portId),
+            eq(documentTemplates.templateType, doc.documentType),
+          ),
+        })
+      : null;
+    templateCadenceDays = templateRow?.reminderCadenceDays ?? null;
 
-  if (!pendingSigner) return false;
+    const lastReminder = await db.query.documentEvents.findFirst({
+      where: and(
+        eq(documentEvents.documentId, documentId),
+        eq(documentEvents.eventType, 'reminder_sent'),
+      ),
+      orderBy: (de, { desc }) => [desc(de.createdAt)],
+    });
+
+    const due = isReminderDue({
+      status: doc.status,
+      documensoId: doc.documensoId,
+      remindersDisabled: doc.remindersDisabled,
+      reminderCadenceOverride: doc.reminderCadenceOverride,
+      templateCadenceDays,
+      lastReminderAt: lastReminder?.createdAt ?? null,
+    });
+    if (!due) return { sent: false, reason: 'Cadence cooldown' };
+
+    // Auto only: 9-16 window in port timezone
+    const port = await db.query.ports.findFirst({ where: eq(ports.id, portId) });
+    const timezone = port?.timezone ?? 'UTC';
+    const currentHour = getCurrentHourInTimezone(timezone);
+    if (currentHour < 9 || currentHour >= 16) {
+      return { sent: false, reason: 'Outside 9-16 port-timezone window' };
+    }
+  }
+
+  // Pick the signer to nudge.
+  const pendingSigners = await db
+    .select()
+    .from(documentSigners)
+    .where(and(eq(documentSigners.documentId, documentId), eq(documentSigners.status, 'pending')))
+    .orderBy(sql`${documentSigners.signingOrder} ASC`);
+  if (pendingSigners.length === 0) {
+    return { sent: false, reason: 'No pending signers' };
+  }
+
+  let target = pendingSigners[0]!;
+
+  if (signerId) {
+    const requested = pendingSigners.find((s) => s.id === signerId);
+    if (!requested) {
+      return { sent: false, reason: 'Signer is not pending' };
+    }
+    // Sequential mode: require the lowest pending order.
+    if (requested.signingOrder !== pendingSigners[0]!.signingOrder) {
+      return { sent: false, reason: 'Signer is not next in sequence' };
+    }
+    target = requested;
+  }
 
-  // Send reminder via Documenso
   try {
-    await documensoRemind(doc.documensoId, pendingSigner.id);
+    await documensoRemind(doc.documensoId, target.id, portId);
   } catch (err) {
-    logger.error({ err, documentId, signerId: pendingSigner.id }, 'Failed to send Documenso reminder');
-    return false;
+    logger.error({ err, documentId, signerId: target.id }, 'Documenso reminder failed');
+    return { sent: false, reason: 'Documenso reminder failed' };
   }
 
-  // Record event
   await db.insert(documentEvents).values({
     documentId,
     eventType: 'reminder_sent',
-    signerId: pendingSigner.id,
-    eventData: { signerEmail: pendingSigner.signerEmail, signerRole: pendingSigner.signerRole },
+    signerId: target.id,
+    eventData: {
+      signerEmail: target.signerEmail,
+      signerRole: target.signerRole,
+      auto,
+    },
   });
 
-  return true;
+  return { sent: true, signerId: target.id };
 }
 
+// ─── processReminderQueue ────────────────────────────────────────────────────
+
+/**
+ * Cron entry point. Selects in-flight documents whose effective cadence
+ * (override or template) is set, then attempts auto-fire on each.
+ * `interests.reminderEnabled` is no longer part of the gating — per-doc
+ * `remindersDisabled` is the kill switch instead.
+ */
 export async function processReminderQueue(portId: string): Promise<void> {
-  // Find all documents with status 'sent' or 'partially_signed' linked to interests with reminderEnabled=true
-  const activeInterests = await db.query.interests.findMany({
-    where: and(
-      eq(interests.portId, portId),
-      eq(interests.reminderEnabled, true),
-    ),
-  });
-
-  if (activeInterests.length === 0) return;
-
-  const interestIds = activeInterests.map((i) => i.id);
-
-  const activeDocs = await db.query.documents.findMany({
-    where: and(
-      eq(documents.portId, portId),
-      inArray(documents.status, ['sent', 'partially_signed']),
-      inArray(documents.interestId, interestIds),
-    ),
-  });
+  const activeDocs = await db
+    .select({ id: documents.id })
+    .from(documents)
+    .leftJoin(documentTemplates, eq(documentTemplates.templateType, documents.documentType))
+    .where(
+      and(
+        eq(documents.portId, portId),
+        inArray(documents.status, ['sent', 'partially_signed']),
+        isNotNull(documents.documensoId),
+        eq(documents.remindersDisabled, false),
+        sql`COALESCE(${documents.reminderCadenceOverride}, ${documentTemplates.reminderCadenceDays}) IS NOT NULL`,
+      ),
+    );
 
   for (const doc of activeDocs) {
     try {
-      await sendReminderIfAllowed(doc.id, portId);
+      await sendReminderIfAllowed(doc.id, portId, { auto: true });
     } catch (err) {
-      logger.error({ err, documentId: doc.id, portId }, 'Reminder processing failed for document');
+      logger.error({ err, documentId: doc.id, portId }, 'Reminder processing failed');
     }
   }
 }
diff --git a/tests/unit/services/document-reminders-cadence.test.ts b/tests/unit/services/document-reminders-cadence.test.ts
new file mode 100644
index 0000000..3bdcfeb
--- /dev/null
+++ b/tests/unit/services/document-reminders-cadence.test.ts
@@ -0,0 +1,70 @@
+import { describe, expect, it } from 'vitest';
+
+import { isReminderDue } from '@/lib/services/document-reminders';
+
+const now = new Date('2026-04-28T12:00:00Z');
+
+function args(overrides: Partial<Parameters<typeof isReminderDue>[0]> = {}) {
+  return {
+    status: 'sent' as const,
+    documensoId: 'doc-1',
+    remindersDisabled: false,
+    reminderCadenceOverride: null,
+    templateCadenceDays: 7,
+    lastReminderAt: null,
+    now,
+    ...overrides,
+  };
+}
+
+describe('isReminderDue', () => {
+  it('returns true when no prior reminder exists and cadence is set', () => {
+    expect(isReminderDue(args())).toBe(true);
+  });
+
+  it('returns false when document is completed', () => {
+    expect(isReminderDue(args({ status: 'completed' }))).toBe(false);
+  });
+
+  it('returns false when document has no Documenso id', () => {
+    expect(isReminderDue(args({ documensoId: null }))).toBe(false);
+  });
+
+  it('returns false when reminders are disabled per-doc', () => {
+    expect(isReminderDue(args({ remindersDisabled: true }))).toBe(false);
+  });
+
+  it('returns false when neither override nor template cadence is set', () => {
+    expect(isReminderDue(args({ templateCadenceDays: null }))).toBe(false);
+  });
+
+  it('respects per-doc override over template default', () => {
+    // 1-day override, last fired 12h ago → not due
+    const lastReminderAt = new Date(now.getTime() - 12 * 60 * 60 * 1000);
+    expect(
+      isReminderDue(args({ templateCadenceDays: 7, reminderCadenceOverride: 1, lastReminderAt })),
+    ).toBe(false);
+
+    // 1-day override, last fired 25h ago → due
+    const earlier = new Date(now.getTime() - 25 * 60 * 60 * 1000);
+    expect(
+      isReminderDue(
+        args({
+          templateCadenceDays: 7,
+          reminderCadenceOverride: 1,
+          lastReminderAt: earlier,
+        }),
+      ),
+    ).toBe(true);
+  });
+
+  it('treats template cadence as the fallback when no override', () => {
+    // 7-day template, last fired 6 days ago → not due
+    const lastReminderAt = new Date(now.getTime() - 6 * 24 * 60 * 60 * 1000);
+    expect(isReminderDue(args({ lastReminderAt }))).toBe(false);
+
+    // 7 days exactly → due
+    const sevenDays = new Date(now.getTime() - 7 * 24 * 60 * 60 * 1000);
+    expect(isReminderDue(args({ lastReminderAt: sevenDays }))).toBe(true);
+  });
+});