diff --git a/phono-server/src/routes/relations_single/mod.rs b/phono-server/src/routes/relations_single/mod.rs
index d88178f..b32fb83 100644
--- a/phono-server/src/routes/relations_single/mod.rs
+++ b/phono-server/src/routes/relations_single/mod.rs
@@ -17,6 +17,7 @@ mod set_filter_handler;
 mod settings_handler;
 mod update_field_handler;
 mod update_field_ordinality_handler;
+mod update_field_table_width_px_handler;
 mod update_portal_name_handler;
 mod update_rel_name_handler;
 mod update_values_handler;
@@ -49,6 +50,10 @@ pub(super) fn new_router() -> Router<App> {
             "/p/{portal_id}/update-field-ordinality",
             post(update_field_ordinality_handler::post),
         )
+        .route(
+            "/p/{portal_id}/update-field-table-width-px",
+            post(update_field_table_width_px_handler::post),
+        )
         .route("/p/{portal_id}/insert", post(insert_handler::post))
         .route(
             "/p/{portal_id}/update-values",
diff --git a/phono-server/src/routes/relations_single/update_field_table_width_px_handler.rs b/phono-server/src/routes/relations_single/update_field_table_width_px_handler.rs
new file mode 100644
index 0000000..90f0261
--- /dev/null
+++ b/phono-server/src/routes/relations_single/update_field_table_width_px_handler.rs
@@ -0,0 +1,95 @@
+use axum::{
+    Json, debug_handler,
+    extract::{Path, State},
+    response::{IntoResponse as _, Response},
+};
+use phono_models::{
+    accessors::{Accessor as _, Actor, portal::PortalAccessor},
+    field::Field,
+};
+use serde::Deserialize;
+use serde_json::json;
+use sqlx::postgres::types::Oid;
+use uuid::Uuid;
+use validator::Validate;
+
+use crate::{
+    app::AppDbConn,
+    errors::AppError,
+    extractors::ValidatedForm,
+    user::CurrentUser,
+    workspace_pooler::{RoleAssignment, WorkspacePooler},
+};
+
+#[derive(Debug, Deserialize)]
+pub(super) struct PathParams {
+    portal_id: Uuid,
+    rel_oid: u32,
+    workspace_id: Uuid,
+}
+
+#[derive(Debug, Deserialize, Validate)]
+pub(super) struct FormBody {
+    field_id: Uuid,
+    #[validate(range(min = 160, max = 800))]
+    table_width_px: u16,
+}
+
+/// HTTP POST handler for updating the display width of a [`Field`] in the table
+/// view. This is distinct from `./update-field`, because it is initiated in the
+/// UI by a "drag" interaction. It may make sense to fold this into the
+/// aforementioned endpoint later, if it is modified to handle partial updates.
+///
+/// This handler expects 3 path parameters with the structure described by
+/// [`PathParams`].
+///
+/// Note that unlike [`super::update_field_ordinality_handler::post`], this
+/// endpoint expects to be called asynchronously and thus returns an HTTP 200
+/// response instead of a redirect.
+#[debug_handler(state = crate::app::App)]
+pub(super) async fn post(
+    State(mut pooler): State<WorkspacePooler>,
+    AppDbConn(mut app_db): AppDbConn,
+    CurrentUser(user): CurrentUser,
+    Path(PathParams {
+        portal_id,
+        rel_oid,
+        workspace_id,
+    }): Path<PathParams>,
+    ValidatedForm(FormBody {
+        field_id,
+        table_width_px,
+    }): ValidatedForm<FormBody>,
+) -> Result<Response, AppError> {
+    // FIXME CSRF
+
+    let mut workspace_client = pooler
+        .acquire_for(workspace_id, RoleAssignment::User(user.id))
+        .await?;
+
+    let portal = PortalAccessor::new()
+        .id(portal_id)
+        .as_actor(Actor::User(user.id))
+        .verify_workspace_id(workspace_id)
+        .verify_rel_oid(Oid(rel_oid))
+        .verify_rel_ownership()
+        .using_app_db(&mut app_db)
+        .using_workspace_client(&mut workspace_client)
+        .fetch_one()
+        .await?;
+
+    // Ensure field exists and belongs to portal.
+    Field::belonging_to_portal(portal.id)
+        .with_id(field_id)
+        .fetch_one(&mut app_db)
+        .await?;
+
+    Field::update()
+        .id(field_id)
+        .table_width_px(table_width_px.into())
+        .build()?
+        .execute(&mut app_db)
+        .await?;
+
+    Ok(Json(json!({ "ok": true })).into_response())
+}
diff --git a/static/portal-table.css b/static/portal-table.css
index e551a4f..b86db6a 100644
--- a/static/portal-table.css
+++ b/static/portal-table.css
@@ -57,16 +57,27 @@
 .field-adder__header-lookalike {
   align-items: center;
   background: #0001;
-  border: solid 1px var(--table-header-border-color);
-  border-top: none;
-  border-left: none;
+  border-bottom: solid 1px var(--table-header-border-color);
+  cursor: grab;
   display: flex;
   flex: none;
   font-family: var(--default-font-family--data);
   height: 100%;
   justify-content: space-between;
-  padding: 0.25rem;
+  padding: 4px;
+  padding-left: 8px;
+  padding-right: 0;
   text-align: left;
+  width: calc(var(--column-width) - 8px);
+
+  &:first-child {
+    padding-left: 12px;
+    width: calc(var(--column-width) - 4px);
+  }
+}
+
+.field-adder__header-lookalike {
+  border-right: solid 1px var(--table-header-border-color);
 }
 
 .field-header .basic-dropdown__button {
@@ -78,7 +89,7 @@
 
 .field-header__label {
   overflow: hidden;
-  padding: 4px;
+  padding: 4px 0;
   text-overflow: ellipsis;
   white-space: nowrap;
 }
@@ -104,6 +115,25 @@
   position: absolute;
 }
 
+.field-resize-handle {
+  background: #0001;
+  border-bottom: solid 1px var(--table-header-border-color);
+  cursor: col-resize;
+  height: 100%;
+  width: 8px;
+
+  .field-resize-handle__v-border {
+    border-left: solid 1px var(--table-header-border-color);
+    height: 100%;
+    margin-left: 3px;
+    width: 1px;
+  }
+
+  &:nth-last-child(1 of .field-resize-handle) {
+    width: 4px;
+  }
+}
+
 /* ======== Component: Field Adder ======== */
 
 .field-adder {
diff --git a/svelte/src/field-header.svelte b/svelte/src/field-header.svelte
index 57ca5d7..61a5a7d 100644
--- a/svelte/src/field-header.svelte
+++ b/svelte/src/field-header.svelte
@@ -3,6 +3,9 @@
   import { type FieldInfo } from "./field.svelte";
   import FieldDetails from "./field-details.svelte";
 
+  const MAX_COL_WIDTH_PX = 800;
+  const MIN_COL_WIDTH_PX = 160;
+
   type Props = {
     field: FieldInfo;
     index: number;
@@ -11,6 +14,7 @@
     ondragover?(ev: DragEvent): unknown;
     ondragstart?(ev: DragEvent): unknown;
     ondrop?(ev: DragEvent): unknown;
+    onresize?(width_px: number): unknown;
   };
 
   let {
@@ -21,6 +25,7 @@
     ondragover,
     ondragstart,
     ondrop,
+    onresize,
   }: Props = $props();
 
   const original_label_value = field.field.table_label;
@@ -30,6 +35,7 @@
   let field_config_dialog_element = $state<HTMLDialogElement | undefined>();
   let name_value = $state(field.field.name);
   let label_value = $state(field.field.table_label ?? "");
+  let resize_drag_x_start = $state<number | undefined>();
 
   $effect(() => {
     field.field.table_label = label_value === "" ? undefined : label_value;
@@ -46,7 +52,7 @@
   {ondragstart}
   {ondrop}
   role="columnheader"
-  style:width={`${field.field.table_width_px}px`}
+  style:--column-width={`${field.field.table_width_px}px`}
   tabindex={0}
 >
   <div class="field-header__label">
@@ -100,6 +106,33 @@
     </menu>
   </BasicDropdown>
 </div>
+<div
+  class="field-resize-handle"
+  draggable={true}
+  ondragstart={(ev) => {
+    resize_drag_x_start = ev.layerX;
+  }}
+  ondragend={(ev) => {
+    if (resize_drag_x_start !== undefined) {
+      onresize?.(
+        Math.min(
+          MAX_COL_WIDTH_PX,
+          Math.max(
+            MIN_COL_WIDTH_PX,
+            field.field.table_width_px + ev.layerX - resize_drag_x_start,
+          ),
+        ),
+      );
+      resize_drag_x_start = undefined;
+    }
+  }}
+  role="separator"
+  aria-valuenow={field.field.table_width_px}
+  aria-valuemin={MIN_COL_WIDTH_PX}
+  aria-valuemax={MAX_COL_WIDTH_PX}
+>
+  <div class="field-resize-handle__v-border"></div>
+</div>
 
 <dialog bind:this={remove_field_dialog_element} class="dialog">
   <form method="post" action="remove-field">
diff --git a/svelte/src/table-viewer.webc.svelte b/svelte/src/table-viewer.webc.svelte
index 162543d..aa8825d 100644
--- a/svelte/src/table-viewer.webc.svelte
+++ b/svelte/src/table-viewer.webc.svelte
@@ -171,6 +171,22 @@
     form.submit();
   }
 
+  function update_field_table_width_px(
+    field_index: number,
+    new_width_px: number,
+  ) {
+    if (lazy_data?.fields[field_index]) {
+      lazy_data.fields[field_index].field.table_width_px = new_width_px;
+      fetch("update-field-table-width-px", {
+        method: "post",
+        headers: {
+          "Content-Type": "application/x-www-form-urlencoded",
+        },
+        body: `field_id=${encodeURIComponent(lazy_data.fields[field_index].field.id)}&table_width_px=${new_width_px}`,
+      }).catch(console.error);
+    }
+  }
+
   // -------- Updates and Effects -------- //
 
   function set_selections(arr: Coords[]) {
@@ -635,6 +651,9 @@
                 });
               }
             }}
+            onresize={(new_width_px) => {
+              update_field_table_width_px(field_index, new_width_px);
+            }}
           />
         {/each}
         <div class="table-viewer__header-actions">