Summary: NTT Docomo, Japan’s largest mobile carrier, will raise the monthly fee on many of its plans from 1 December 2026. Most of the plans on the list are older plans that you can no longer sign up for, such as eximo and Gigaho (up ¥550 a month) and irumo (up ¥110 to ¥330). The popular online plan ahamo also changes: the 30GB plan becomes a three-step plan starting at 40GB for ¥3,135, which is ¥165 more than today. You do not need to do anything for the new prices to apply. If you use ahamo, the most important thing is a new 40GB data cap that Docomo will switch on automatically. This article explains what is changing, who is affected, and what to check before the end of November.
What is changing
Docomo announced the changes on 25 September 2026. It gave the reason as the rising cost of goods and labour, and said the price revision is “mainly” for plans that are already closed to new customers. The new prices apply from the December 2026 usage month.
There are three separate changes, and they affect different people:
- Higher fees on older plans. If you signed up years ago and never changed plan, your monthly base fee goes up.
- A new ahamo. The single 30GB plan and the “Oomori” (large-size) add-on are replaced by a price that depends on how much data you use in the month.
- More data abroad. On ahamo and the Docomo MAX plans, the data you can use overseas rises from 30GB to 40GB a month.
Who is affected, and by how much
The amounts below are the increases in the monthly base fee, including consumption tax, as listed in Docomo’s press release.
- +¥550 a month: eximo, eximo Poikatsu, 5G Gigaho, 5G Gigaho Premier, Gigaho and Gigaho Premier.
- +¥330 a month: irumo 3GB, 6GB and 9GB, 5G Gigalite and Gigalite, and the older Kakehodai (flat-rate calling) plans, among others.
- +¥165 a month: ahamo (see the next section).
- +¥110 a month: irumo 0.5GB, several plans for children and basic “keitai” phones, and data-sharing add-on plans.
Plans sold under the OCN Mobile ONE brand are also on the list. The plans that Docomo sells to new customers today, Docomo MAX and Docomo Poikatsu MAX, are not on the price-increase list. Docomo says the monthly fee of Docomo mini is also not changing.
If you pay for more than one line, for example for a partner or children, the increase applies to each line on an affected plan.
What happens to ahamo
ahamo is Docomo’s online-only plan: you sign up and get support mainly through the website and app. Today it costs ¥2,970 a month for 30GB. With the “Oomori” add-on (+80GB for ¥1,980), it is ¥4,950 for 110GB.
From 1 December, ahamo has three steps, and the price is set by the data you actually use in the month:
- Step 1: up to 40GB — ¥3,135
- Step 2: over 40GB, up to 60GB — ¥4,125
- Step 3: over 60GB, up to 120GB — ¥5,115
So a light user pays ¥165 more but gets 10GB more. A heavy user who paid ¥4,950 for 110GB pays ¥5,115 for up to 120GB. The Oomori add-on ends on 30 November and is removed automatically. The call charges and phone instalments are separate, as before.
The automatic 40GB cap
This is the part most likely to surprise people. If you have ahamo on 1 November 2026 and you do not use the Oomori add-on, Docomo will turn on a free “upper limit” option set to 40GB on 1 December. With the cap on, you stay at Step 1 and pay ¥3,135. When you reach 40GB, your speed drops to a maximum of 1Mbps until the end of the month. You do not move up to Step 2.
If you would rather keep full speed and pay for Step 2 or Step 3 in a heavy month, you can remove the cap in the ahamo app or My docomo. You can also set the cap at 60GB instead. Docomo sends an SMS before each step only if you have signed up for its data-usage notice service, so check that setting too.
When you will notice it
The new fees apply to usage from 1 December 2026. Docomo bills by usage month, so the first bill that shows the higher amount is the bill for your December usage. Docomo says no application or paperwork is needed: your plan as of 30 November simply moves to the new price.
What you can do now
- Find your plan name. Log in to My docomo (or the ahamo app) and look for the name of your current plan. Docomo’s price-revision page has a tool: choose your plan and it shows the fee up to November and from December.
- Check your real data use. Look at the last three months. If you usually use less than 40GB on ahamo, the automatic cap will not change much for you. If you often go over, decide whether you want the cap or full speed.
- If you are on an older plan, compare with a current one. Because the increase targets closed plans, moving to a plan that is sold today may cost the same or less. Compare the total including discounts you actually qualify for, not the advertised lowest price.
- Before you switch carrier, check the basics. Leaving Docomo means moving your number (MNP), and some discounts are linked to Docomo Hikari internet or a d Card. Also check whether your phone is paid off.
- Going home for the holidays? From December, ahamo and Docomo MAX users can use up to 40GB abroad. After 15 days abroad, speed drops to 128kbps, but a new day-by-day add-on (¥980 per 24 hours, as listed by Docomo) keeps normal speed on longer trips.
If you are not with Docomo
This change is only for Docomo, ahamo and OCN Mobile ONE lines, including lines from the ahamo partner brand JAL Mobile. If you use another company, including a budget SIM that runs on the Docomo network, your price is set by that company, not by this announcement. Still, prices for phones, gas and parcels are rising in several places this year. If you have not looked at your phone contract for a year or two, it is worth logging in once and checking your plan name, your data use and what you pay each month.
For help choosing a first phone number in Japan, see our guide below.
FAQ
Do I need to apply or sign anything for the new prices?
No. Docomo says no procedure is needed. The plan you have on 30 November moves to the new price from 1 December.
I have ahamo. Will my bill jump to ¥5,115 if I use a lot of data?
Not if the automatic 40GB cap is on. With the cap, you pay ¥3,135 and your speed slows after 40GB. The price only steps up if you remove the cap or set it higher. Oomori users do not get the automatic cap, because their current plan already includes more data.
Is Docomo MAX or Docomo mini going up?
Docomo MAX and Docomo Poikatsu MAX are not on the list of plans with higher fees. Docomo says the monthly fee of Docomo mini is not being revised either.
I use the ahamo Oomori add-on. What happens to me?
Oomori ends on 30 November and is removed automatically. From December you pay by step: up to ¥5,115 for up to 120GB. Because you already use a lot of data, Docomo does not switch on the automatic 40GB cap for you.
Which plans get the bigger overseas data allowance?
From 1 December, the overseas allowance rises from 30GB to 40GB a month on ahamo, Docomo MAX, Docomo Poikatsu MAX and the business plan Docomo Biz Data Unlimited. The day-by-day add-on for trips longer than 15 days is for the same plans, and you apply for it in My docomo or on the ahamo site.
Related reading
- Getting a Japanese phone number as a new resident: voice SIM vs data-only
- Tokyo Gas raises its basic charge by ¥150
日本語で読む: ドコモが12月1日に旧プランを値上げ（Japanese version）
