diff --git a/src/api/scheduleApi.ts b/src/api/scheduleApi.ts
index 4a93b3a..348b790 100644
--- a/src/api/scheduleApi.ts
+++ b/src/api/scheduleApi.ts
@@ -2,6 +2,7 @@ import { apiRequest } from "./apiClient";
 import { endpoints } from "./endpoints";
 import type { BackendPreference } from "@/types/backend";
 import type {
+  ClockInRequest,
   ClockOutRequest,
   GenerateWeeklyScheduleRequest,
   Schedule,
@@ -28,10 +29,12 @@ export function generateWeeklySchedule(
 export function clockIn(
   backendPreference: BackendPreference,
   employeeId: number,
+  request: ClockInRequest,
 ): Promise<Schedule> {
   return apiRequest<Schedule>(endpoints.employeeClockIn(employeeId), {
     backendPreference,
     method: "POST",
+    body: JSON.stringify(request),
   });
 }
 
diff --git a/src/pages/CompaniesPage.module.scss b/src/pages/CompaniesPage.module.scss
index 58db83d..faf20e1 100644
--- a/src/pages/CompaniesPage.module.scss
+++ b/src/pages/CompaniesPage.module.scss
@@ -1,5 +1,6 @@
 .primaryButton,
-.secondaryButton {
+.secondaryButton,
+.dangerButton {
   border: 0;
   border-radius: 999px;
   padding: 12px 18px;
@@ -19,6 +20,16 @@
   box-shadow: inset 0 0 0 1px #d9e1ec;
 }
 
+.dangerButton {
+  background: #dc2626;
+  color: #ffffff;
+
+  &:disabled {
+    cursor: not-allowed;
+    opacity: 0.65;
+  }
+}
+
 .companyGrid {
   display: grid;
   grid-template-columns: repeat(3, minmax(0, 1fr));
@@ -110,6 +121,24 @@
   }
 }
 
+.confirmation {
+  display: grid;
+  gap: 18px;
+
+  p {
+    margin: 0;
+    color: #293548;
+    line-height: 1.6;
+  }
+}
+
+.confirmationActions {
+  display: flex;
+  justify-content: flex-end;
+  gap: 10px;
+  flex-wrap: wrap;
+}
+
 .error {
   color: #b91c1c;
   font-weight: 700;
diff --git a/src/pages/CompaniesPage.tsx b/src/pages/CompaniesPage.tsx
index e30ee8e..d6520d2 100644
--- a/src/pages/CompaniesPage.tsx
+++ b/src/pages/CompaniesPage.tsx
@@ -26,6 +26,7 @@ export function CompaniesPage({ backendPreference }: CompaniesPageProps) {
   const [employeeNamesByCompany, setEmployeeNamesByCompany] = useState<EmployeeNamesByCompany>({});
   const [users, setUsers] = useState<Employee[]>([]);
   const [companyName, setCompanyName] = useState("");
+  const [companyToDelete, setCompanyToDelete] = useState<Company | null>(null);
   const [selectedCompany, setSelectedCompany] = useState<Company | null>(null);
   const [selectedEmployeeId, setSelectedEmployeeId] = useState("");
   const [error, setError] = useState("");
@@ -107,18 +108,17 @@ export function CompaniesPage({ backendPreference }: CompaniesPageProps) {
     }
   }
 
-  async function handleDeleteCompany(company: Company) {
-    const shouldDelete = window.confirm(`Delete ${company.name}?`);
-
-    if (!shouldDelete) {
+  async function handleDeleteCompany() {
+    if (!companyToDelete) {
       return;
     }
 
-    setDeletingCompanyId(company.id);
+    setDeletingCompanyId(companyToDelete.id);
     setError("");
 
     try {
-      await deleteCompany(backendPreference, company.id);
+      await deleteCompany(backendPreference, companyToDelete.id);
+      setCompanyToDelete(null);
       await loadCompanies();
     } catch (deleteError) {
       setError(deleteError instanceof Error ? deleteError.message : "Unable to delete company");
@@ -151,7 +151,7 @@ export function CompaniesPage({ backendPreference }: CompaniesPageProps) {
               <button
                 className={styles.deleteButton}
                 disabled={deletingCompanyId === company.id}
-                onClick={() => void handleDeleteCompany(company)}
+                onClick={() => setCompanyToDelete(company)}
                 type="button"
                 aria-label={`Delete ${company.name}`}
               >
@@ -196,31 +196,75 @@ export function CompaniesPage({ backendPreference }: CompaniesPageProps) {
         </Modal>
       ) : null}
 
-      {selectedCompany ? (
-        <Modal
-          title={`Add users to ${selectedCompany.name}`}
-          onClose={() => setSelectedCompany(null)}
-        >
-          <form className={styles.form} onSubmit={handleAssignEmployee}>
-            <label>
-              Existing user
-              <select
-                value={selectedEmployeeId}
-                onChange={(event) => setSelectedEmployeeId(event.target.value)}
-                required
+      {selectedCompany
+        ? (() => {
+            const assignedNames = new Set(employeeNamesByCompany[selectedCompany.id] ?? []);
+            const availableUsers = users.filter(
+              (user) => !assignedNames.has(`${user.name} ${user.last_name}`),
+            );
+
+            return (
+              <Modal
+                title={`Add users to ${selectedCompany.name}`}
+                onClose={() => setSelectedCompany(null)}
               >
-                <option value="">Select a user</option>
-                {users.map((user) => (
-                  <option key={user.id} value={user.id}>
-                    {user.name} {user.last_name}
-                  </option>
-                ))}
-              </select>
-            </label>
-            <button className={styles.primaryButton} disabled={isSaving} type="submit">
-              {isSaving ? "Saving..." : "Assign user"}
-            </button>
-          </form>
+                <form className={styles.form} onSubmit={handleAssignEmployee}>
+                  {availableUsers.length === 0 ? (
+                    <p className={styles.muted}>All users are in a company</p>
+                  ) : (
+                    <label>
+                      Existing user
+                      <select
+                        value={selectedEmployeeId}
+                        onChange={(event) => setSelectedEmployeeId(event.target.value)}
+                        required
+                      >
+                        <option value="">Select a user</option>
+                        {availableUsers.map((user) => (
+                          <option key={user.id} value={user.id}>
+                            {user.name} {user.last_name}
+                          </option>
+                        ))}
+                      </select>
+                    </label>
+                  )}
+                  <button
+                    className={styles.primaryButton}
+                    disabled={isSaving || availableUsers.length === 0}
+                    type="submit"
+                  >
+                    {isSaving ? "Saving..." : "Assign user"}
+                  </button>
+                </form>
+              </Modal>
+            );
+          })()
+        : null}
+
+      {companyToDelete ? (
+        <Modal title="Delete company" onClose={() => setCompanyToDelete(null)}>
+          <div className={styles.confirmation}>
+            <p>
+              Delete <strong>{companyToDelete.name}</strong>? This action cannot be undone.
+            </p>
+            <div className={styles.confirmationActions}>
+              <button
+                className={styles.secondaryButton}
+                onClick={() => setCompanyToDelete(null)}
+                type="button"
+              >
+                Cancel
+              </button>
+              <button
+                className={styles.dangerButton}
+                disabled={deletingCompanyId === companyToDelete.id}
+                onClick={() => void handleDeleteCompany()}
+                type="button"
+              >
+                {deletingCompanyId === companyToDelete.id ? "Deleting..." : "Delete company"}
+              </button>
+            </div>
+          </div>
         </Modal>
       ) : null}
     </>
diff --git a/src/pages/UsersPage.module.scss b/src/pages/UsersPage.module.scss
index c4b3daa..9b51569 100644
--- a/src/pages/UsersPage.module.scss
+++ b/src/pages/UsersPage.module.scss
@@ -20,6 +20,29 @@
   box-shadow: inset 0 0 0 1px #d9e1ec;
 }
 
+.actionGroup {
+  display: flex;
+  flex-wrap: wrap;
+  gap: 8px;
+}
+
+.actionButton {
+  border: 0;
+  border-radius: 999px;
+  padding: 8px 11px;
+  background: #eef4ff;
+  color: #1d4ed8;
+  cursor: pointer;
+  font-size: 0.82rem;
+  font-weight: 700;
+  white-space: nowrap;
+
+  &:disabled {
+    cursor: not-allowed;
+    opacity: 0.45;
+  }
+}
+
 .tableCard {
   overflow: hidden;
   background: #ffffff;
diff --git a/src/pages/UsersPage.tsx b/src/pages/UsersPage.tsx
index 578ca4e..2230617 100644
--- a/src/pages/UsersPage.tsx
+++ b/src/pages/UsersPage.tsx
@@ -1,7 +1,7 @@
 import { useCallback, useEffect, useMemo, useState } from "react";
 import type { FormEvent } from "react";
 import { getCompanies } from "@api/companiesApi";
-import { getWeekSchedule } from "@api/scheduleApi";
+import { clockIn, clockOut, getWeekSchedule } from "@api/scheduleApi";
 import { createUser, getUsers, updateUserPreference } from "@api/usersApi";
 import { Modal } from "@components/Modal";
 import { PageHeader } from "@components/PageHeader";
@@ -66,6 +66,9 @@ export function UsersPage({ backendPreference }: UsersPageProps) {
   const [error, setError] = useState("");
   const [isAddUserOpen, setIsAddUserOpen] = useState(false);
   const [isPreferenceOpen, setIsPreferenceOpen] = useState(false);
+  const [checkingInUser, setCheckingInUser] = useState<Employee | null>(null);
+  const [checkInDateTime, setCheckInDateTime] = useState("");
+  const [savingActionUserId, setSavingActionUserId] = useState<number | null>(null);
   const [isLoading, setIsLoading] = useState(true);
   const [isSaving, setIsSaving] = useState(false);
 
@@ -153,6 +156,69 @@ export function UsersPage({ backendPreference }: UsersPageProps) {
     }
   }
 
+  function getDayOfWeekFromDateTime(value: string): import("@/types/users").DayOfWeek {
+    const days: import("@/types/users").DayOfWeek[] = [
+      "sunday",
+      "monday",
+      "tuesday",
+      "wednesday",
+      "thursday",
+      "friday",
+      "saturday",
+    ];
+    return days[new Date(value).getDay()];
+  }
+
+  function openCheckInModal(user: Employee) {
+    const now = new Date();
+    const local = new Date(now.getTime() - now.getTimezoneOffset() * 60000)
+      .toISOString()
+      .slice(0, 16);
+    setCheckingInUser(user);
+    setCheckInDateTime(local);
+  }
+
+  async function handleClockIn(event: FormEvent<HTMLFormElement>) {
+    event.preventDefault();
+
+    if (!checkingInUser || !checkInDateTime) {
+      return;
+    }
+
+    setError("");
+    setSavingActionUserId(checkingInUser.id);
+
+    try {
+      await clockIn(backendPreference, checkingInUser.id, {
+        day_of_week: getDayOfWeekFromDateTime(checkInDateTime),
+        enter_time: new Date(checkInDateTime).toISOString(),
+      });
+      setCheckingInUser(null);
+      await loadUsersPage();
+    } catch (saveError) {
+      setError(saveError instanceof Error ? saveError.message : "Unable to check in user");
+    } finally {
+      setSavingActionUserId(null);
+    }
+  }
+
+  async function handleClockOut(userId: number, activeSchedule: Schedule) {
+    setError("");
+    setSavingActionUserId(userId);
+
+    try {
+      await clockOut(backendPreference, userId, {
+        day_of_week: activeSchedule.day_of_week,
+        out_time: new Date().toISOString(),
+      });
+      await loadUsersPage();
+    } catch (saveError) {
+      setError(saveError instanceof Error ? saveError.message : "Unable to check out user");
+    } finally {
+      setSavingActionUserId(null);
+    }
+  }
+
   return (
     <>
       <PageHeader
@@ -191,12 +257,16 @@ export function UsersPage({ backendPreference }: UsersPageProps) {
                 <th>Check in</th>
                 <th>Check out</th>
                 <th>Days worked</th>
+                <th>Actions</th>
               </tr>
             </thead>
             <tbody>
               {users.map((user) => {
                 const userSchedules = schedulesByUser[user.id] ?? [];
                 const status = getUserStatus(userSchedules);
+                const activeSchedule = userSchedules.find(
+                  (schedule) => schedule.enter_time && !schedule.out_time,
+                );
                 const latestSchedule = userSchedules.at(-1);
                 const company = companies.find((item) => item.id === user.company_id);
                 const daysWorked = new Set(
@@ -210,11 +280,15 @@ export function UsersPage({ backendPreference }: UsersPageProps) {
                     className={selectedUserId === user.id ? styles.selectedRow : ""}
                     key={user.id}
                     onClick={() => setSelectedUserId(user.id)}
+                    title="Double click to edit user information"
                   >
                     <td>
                       {user.name} {user.last_name}
                     </td>
-                    <td>{company?.name ?? `Company #${user.company_id}`}</td>
+                    <td>
+                      {company?.name ??
+                        (user.company_id ? `Company #${user.company_id}` : "Unassigned")}
+                    </td>
                     <td>{user.preference}</td>
                     <td>
                       <span className={`${styles.status} ${styles[status]}`}>
@@ -224,6 +298,35 @@ export function UsersPage({ backendPreference }: UsersPageProps) {
                     <td>{formatDateTime(latestSchedule?.enter_time ?? null)}</td>
                     <td>{formatDateTime(latestSchedule?.out_time ?? null)}</td>
                     <td>{daysWorked}</td>
+                    <td>
+                      <div className={styles.actionGroup}>
+                        <button
+                          className={styles.actionButton}
+                          disabled={Boolean(activeSchedule) || savingActionUserId === user.id}
+                          onClick={(event) => {
+                            event.stopPropagation();
+                            openCheckInModal(user);
+                          }}
+                          type="button"
+                        >
+                          Check in
+                        </button>
+                        <button
+                          className={styles.actionButton}
+                          disabled={!activeSchedule || savingActionUserId === user.id}
+                          onClick={(event) => {
+                            event.stopPropagation();
+
+                            if (activeSchedule) {
+                              void handleClockOut(user.id, activeSchedule);
+                            }
+                          }}
+                          type="button"
+                        >
+                          Check out
+                        </button>
+                      </div>
+                    </td>
                   </tr>
                 );
               })}
@@ -314,6 +417,37 @@ export function UsersPage({ backendPreference }: UsersPageProps) {
           </form>
         </Modal>
       ) : null}
+
+      {checkingInUser ? (
+        <Modal
+          title={`Check in ${checkingInUser.name} ${checkingInUser.last_name}`}
+          onClose={() => setCheckingInUser(null)}
+        >
+          <form className={styles.form} onSubmit={handleClockIn}>
+            <label>
+              Date and time
+              <input
+                type="datetime-local"
+                value={checkInDateTime}
+                onChange={(event) => setCheckInDateTime(event.target.value)}
+                required
+              />
+            </label>
+            <p className={styles.muted}>
+              Day of week will be derived as{" "}
+              {checkInDateTime ? getDayOfWeekFromDateTime(checkInDateTime) : "--"} from the selected
+              date.
+            </p>
+            <button
+              className={styles.primaryButton}
+              disabled={savingActionUserId === checkingInUser.id}
+              type="submit"
+            >
+              {savingActionUserId === checkingInUser.id ? "Saving..." : "Check in"}
+            </button>
+          </form>
+        </Modal>
+      ) : null}
     </>
   );
 }
diff --git a/src/types/schedule.ts b/src/types/schedule.ts
index bac800d..ff06b10 100644
--- a/src/types/schedule.ts
+++ b/src/types/schedule.ts
@@ -19,6 +19,11 @@ export type CreateScheduleRequest = {
   out_time: string;
 };
 
+export type ClockInRequest = {
+  day_of_week: DayOfWeek;
+  enter_time: string;
+};
+
 export type ClockOutRequest = {
   day_of_week: DayOfWeek;
   out_time: string;
diff --git a/src/types/users.ts b/src/types/users.ts
index a35e4cd..7e6c504 100644
--- a/src/types/users.ts
+++ b/src/types/users.ts
@@ -2,7 +2,7 @@ export type WorkTime = "morning" | "afternoon" | "evening";
 
 export type Employee = {
   id: number;
-  company_id: number;
+  company_id: number | null;
   name: string;
   last_name: string;
   preference: WorkTime;