Raising the rent legally: deadlines, form and indices

When a landlord can raise the rent

There is no single legal basis for a rent increase that fits every contract. It works one way for an occasional lease (najem okazjonalny), another way for an ordinary residential lease, and differently again for an institutional lease. The differences come down to how far the Tenant Protection Act (ustawa o ochronie praw lokatorów) shields the tenant and which of its provisions have been switched off for a given type of contract. Before you work out the new rate, establish which regime you are operating in. That decides both the procedure and the limits of the change.

The second variable: how long the contract runs. A fixed-term contract locks in the rate until the end of the agreed period. Unless the contract contains an indexation clause or another provision that expressly allows the charges to change during its term. Without that, all you have left is an annex, meaning a matching declaration from both sides - and the tenant does not have to sign it.

An open-ended contract gives the landlord a completely different tool: notice of a change in the rent amount. This declaration changes the rate itself, it does not end the contract. The tenancy carries on, only the new amount applies once the notice period has run. And here comes the classic slip-up - the landlord sends a letter headed “notice of termination”, then wonders why the tenant has started browsing listings. Some disputes about the bill are not about rent at all, but about how utilities are settled.

The rule I repeat in every conversation like this: an increase with no footing in the contract or in the act is ineffective. It is not cured by the tenant’s silence, nor by the fact that they paid more for six months. The absence of a written objection does not create a new rate. In a dispute over arrears, what counts is the contract and the declarations that were effectively delivered. That is all.

• Fixed term with no indexation clause: the rate is frozen until the contract ends, a change is only possible by annex.
• Fixed term with a clause: recalculation using the mechanism written into the contract, on the dates the contract sets out.
• Open-ended term: notice of a change in the rent amount as a separate letter, the contract carries on.
• Institutional and occasional lease: how far the tenant is protected depends on whether the formal requirements were met when the contract was signed.

Deadlines: how many months of notice and from when to count

Notice of a change in the rent amount has to be served by the end of a calendar month at the latest, keeping the notice period set for that type of contract. So: the delivery date of the letter marks the starting point, not the moment from which you may charge more. A full notice period runs between the two, counted in calendar months. A letter delivered on the 15th only starts working once that month has closed.

The new rate takes effect once the notice period has run. Until then the tenant pays the old amount and is not in default, even if the letter with the higher figure is already sitting on their table. A landlord who issues a settlement at the new rate any earlier creates a discrepancy they will have to correct anyway.

Frequency is a separate matter. The next change of rate requires waiting out a period counted from the previous increase, so the history of changes matters for more than the archive. You do not know the date of the previous notice? Then you cannot reliably establish whether the new letter will work at all.

Reports from tenanto users point to one mistake above all others: counting the deadline from the day of a phone call or a message on a chat app. The landlord remembers the moment they “mentioned the increase”, not the moment of effective delivery. The gap can run to two months, and it usually surfaces at the annual settlement or when the deposit is returned.

Tip: right after sending, put two dates in the contract calendar - the day of delivery and the first month settled at the new rate. Straight away, the same day. Because in three weeks you will no longer be sure which month is the “new” one.

1. Establish the notice period that applies to your type of contract.
2. Send the letter so that delivery happens before the end of the month.
3. Keep proof of delivery with the date.
4. Count the full notice period from the end of the month of delivery.
5. Write down the first month charged at the new rate.

The form of a notice changing the rent amount

The act requires written form on pain of nullity. A text message, a message on a chat app, an email without a qualified signature, an arrangement made while handing over the keys - none of that passes. A letter in the wrong form produces no legal effect, and it makes no difference how clearly it was worded. The easiest mistake to avoid, and I see it regularly.

Form alone is not enough, though, if the content has holes in it. A proper letter states the current rate, the new rate, the date it takes effect and the basis for the increase - a provision of the act or a specific clause of the contract. Leave any of these out and you have a ready-made dispute about what you actually declared.

Proof of delivery decides when the period starts running. In practice what works is a confirmation of receipt for registered mail, a delivery notice where receipt was refused, or the tenant’s signature on a copy handed over in person. Keep the proof of posting too - on its own it does not prove delivery, but it puts the chronology in order.

Several tenants on one contract? The letter goes to each of them separately. Delivery to one co-tenant does not replace delivery to the others, even if they sleep in the same flat and share a letterbox.

The elements whose absence most often gets the letter challenged:

• identification of the flat and the contract it concerns;
• the current and the new rent amount, both as figures;
• the date from which the new rate applies;
• the statutory or contractual basis for the increase;
• separation of the rent from charges outside the landlord’s control;
• the signature of the landlord or their representative, together with the authorisation;
• addressee details matching the party to the contract.

The indices that indexation rests on

The most common contractual mechanism is an indexation clause based on the consumer price index published by Statistics Poland (Główny Urząd Statystyczny, GUS). The trouble is that simply pointing to “the GUS inflation index” is too vague. The office publishes several values and at any given moment they can differ from one another.

And the difference translates straight into money. The annual index describes the change in prices across a whole calendar year against the previous one. The monthly year-on-year index compares a given month with the same month a year earlier. The cumulative one measures the change from the start of the year to the stated month. The contract has to name one specific index, otherwise each side will pick the one that suits it. That really is what happens.

The second axis is who has to act. Automatic indexation works by force of the clause itself - once the index is announced, the rate changes with no further steps. Indexation on request needs a declaration from the landlord within a set deadline, and if there is none, there is simply no recalculation that year. The contract should say plainly which variant applies and what happens once the deadline passes.

Plenty of conflicts come from overlooking the moment of publication. The GUS announcement comes out later than the period it covers. Without a stated reference date it is hard to settle which value should go into the calculation.

And separately there are the charges outside the landlord’s control: utilities, water advances, waste collection, payments to the housing community or cooperative. These follow their own rules, they change on the basis of resolutions and suppliers’ tariffs, and they are not subject to the rent-change notice procedure at all. Lumping them in with a rent increase blurs the picture and makes your position harder to defend if it comes to a dispute.

Justifying the increase and the tenant’s right to demand it

Within the statutory deadline the tenant may demand a written justification for the increase together with the calculation behind it. This right applies whether or not they intend to challenge anything - it mainly serves to establish where the new figure came from. The landlord replies within the deadline set by the act.

Failing to reply costs. A landlord who ignored the demand enters any dispute from a weaker position: they cannot later fall back on arguments they never presented, and the passivity itself tends to be read as a sign that there was no calculation at all. Preparing the justification usually takes half an hour. Putting it right afterwards - a great deal more.

Once the notice arrives, the tenant has three routes. They can accept the new rate and start paying it from the right month. They can challenge the increase by filing a court claim for a ruling that it is unjustified, or justified at a different level. They can also terminate the contract if the new terms do not suit them.

Until the dispute is finally resolved, the previous rate applies, on the terms described in the act. A tenant who paid less during that time is not in arrears - the difference is settled only after the judgment and depending on what it says. A landlord keeping records should mark such a period as disputed, so as not to bury the tenant in payment demands for the months covered by the proceedings.

Three groups of arguments come up again and again in justifications: rising costs of maintaining the flat, spending on renovation or modernisation, and the level of market rates for comparable flats. Each of them gains weight when there is a document behind it - an invoice, a works acceptance protocol, a list of offers from the same neighbourhood.

How to document an increase so you never have to revisit it years later

The full set of evidence for a single increase is short, four items: the letter giving notice of the new rent amount, the proof of posting, the proof of receipt, and an annex or a note attached to the contract with the new rate and the date it applies from. Gathering that on the day you send the letter takes a few minutes. Reconstructing it three years later, when the tenant is disputing arrears, can eat a whole weekend and end with nothing.

A rate history kept in one place also answers the question of when the period allowing the next change expired. Without that chronology the landlord either waits longer than they have to, or sends the letter too early and loses the entire cycle.

In tenanto every flat has its own contract card with the date the rate applies from. Settlements after an increase are calculated from the right month by themselves, with no manual recalculation and no need to watch when the amount on the payment request changes. Previous rates stay visible in the flat’s history, so you check the date of the last change with a glance at the card instead of digging through your inbox.

With one flat a spreadsheet is honestly enough. With several flats and different dates on which rates take effect it starts to fall apart: formulas do not know about cut-off dates, and monthly columns do not tell rent apart from advances. The most frequent report from new users is exactly this, settlements gone wrong after a rent change - the amounts in the spreadsheet do not match what actually landed in the account.

An account for a single flat is free in tenanto with no time limit, so you can keep a rate history from the very first contract. Well before a second flat shows up and there is a real need to manage a larger portfolio.

The most common landlord mistakes when raising the rent

First and most expensive: raising the rate during a fixed-term contract that has no indexation clause. Such a change does not work, no matter how nicely the letter is written or how sensible the justification is. And if the tenant paid more, they can later demand the overpayment back.

Second: agreeing the new amount verbally and adding it to the settlement with no letter. The landlord assumes that since the conversation went well, the paperwork is a formality. In a dispute they are left with two versions of events and zero evidence of when the change was meant to take effect.

Third: mixing a rent increase with a rise in utility advances in a single figure. The tenant only sees a bigger sum to pay and has no idea what actually changed. And if they demand a justification, the figure will have to be broken down anyway - so why put it off.

Fourth: charging the new rate from the month the letter was sent instead of after the notice period has run. That creates a difference the landlord sees as arrears and the tenant as an arithmetic error. Payment demands sent on that basis wreck the relationship for no reason at all.

Fifth, and the last to surface: no archive of previous letters. Without one you cannot show when the previous change took place, and in a dispute about how often the rent was raised that is the piece of information that settles the case.

• Changing the rate with no basis in the contract on a fixed-term agreement.
• Verbal arrangements instead of a letter with proof of delivery.
• One combined figure instead of a split between rent and charges outside the landlord’s control.
• The deadline counted from posting rather than from delivery.
• Documents scattered across emails and chat apps.

FAQ and summary

Does the tenant have to agree to a rent increase?

No, their consent is not needed - as long as the landlord effectively gave notice of the change in the rent amount: in writing, keeping the deadline, and with an existing statutory or contractual basis. The tenant signs nothing in that case, and the new rate takes effect once the notice period has run. They do have rights of their own: they can demand a written justification, challenge the increase in court, or terminate the contract and move out on the terms it sets out. It looks different with a fixed-term contract that has no indexation clause - there a change of rate requires an annex, meaning genuine agreement from both sides.

The whole procedure comes down to five conditions that all have to be met together:. When a tenant refuses the increase, the next step is often ending the tenancy, where the deadlines matter.

1. the basis for the increase follows from the contract or from the act;
2. the declaration is in written form;
3. there is proof of delivery to every tenant;
4. the deadline runs from delivery, not from posting or from a conversation;
5. the indexation index is named explicitly, along with its reference point.

Orderly documentation of rates puts out most disputes before they get going. When a landlord can produce the letter, the proof of receipt and the date the new amount took effect within seconds, a conversation about arrears ends with the facts established. When those documents are missing, the same conversation ends up in court. And it is usually not about whether the increase was justified, but about whether it ever took effect at all.