Is it permissible by law to charge tenants for additional roommates?
<p><strong>Preface:</strong></p>

<p>I plan to purchase a single family home and rent it out to university students. Originally, it was expected that there would be one student per room (as communal areas would be sized according to how many rooms there are); however, some students expressing interest in renting have mentioned that they'd like their significant other to also live with them.</p>

<p>This presents a slight problem to my system. The house is meant for <em>X</em> amount of people, where there would now be <em>Z</em> amount. Utility usage would increase; additional space would be used to accommodate their possessions; also, it would increase liability on my end.</p>

<p>I wouldn't mind this situation if I'm making up for it in additional income. To reasonable limits of course. Five people in a tiny room would be quite silly.</p>

<p><strong>Edit:</strong></p>

<p>For the purposes of this question, consider only the actual act of charging the tenants extra simply for adding another person to the room. I’m not concerned with zoning and other occupancy restrictions.</p>

<p><strong>Research:</strong></p>

<p>I have been referencing <a href="https://www.govinfo.gov/content/pkg/USCODE-2011-title42/pdf/USCODE-2011-title42-chap45.pdf" rel="nofollow noreferrer">Title 42 of US Code (USC) under chapter 45</a>.</p>

<p>"Sec. §3604.a" states that it is unlawful:</p>

<blockquote>
  <p>To refuse to sell or rent after the making
  of a bona fide offer, or to refuse to negotiate for
  the sale or rental of, or otherwise make unavailable or deny, a dwelling to any person because of
  race, color, religion, sex, familial status, or national origin.</p>
</blockquote>

<p>What I'm reading from this, is that I cannot alter (increase) my proposed baseline rate once I'm aware of an individual having familial status.</p>

<p>"Sec. §3602.k" says:</p>

<blockquote>
  <p>"Familial status" means one or more individuals (who have not attained the age of 18 years) being domiciled with</p>
  
  <ol>
  <li><p>a parent or another person having legal custody of such individual or individuals</p>
  
  <p><strong>or</strong></p></li>
  <li><p>the designee of such parent or other person having such custody, with the written permission of such parent or other person.</p></li>
  </ol>
</blockquote>

<p>Here looks like the <em>sole</em> definition of familial status; but I'm not quite sure if its only a contextual fragment; meaning there might be other ways of interpreting what that status might be. </p>

<p><strong>Summary:</strong></p>

<p>It <em>seems</em> that familial status only applies to parents who are in custody of a minor.</p>

<p>Is that really the case? Do spouses, significant others, or other familiar relationships not matter? Are there states that tack on additional discrimination criteria? </p>

<p>Am I able to charge my tenants an extra fee for adding another resident to the their room and subsequently my property?</p>

<p>Your actual inquiry boils down to the statutory interpretation of the aforementioned excerpts. A surcharge for additional roommates <em>does not</em> violate these statutes, since "<em>being domiciled with</em>" does not mean and does not imply "<em>living in the same bedroom</em>".</p>

<p>Your knowledge that "<em>X is Y'parent</em>" is not discouraging you from renting your unit to them. In fact, I gather that you would gladly allow each one to rent their own separate bedroom (that is, one room per individual) if you have enough rooms available. This means that you are neither <em>refusing</em> to rent nor refusing to <em>reasonably negotiate</em> rental on the basis of <em>familial status</em>.</p>

<p>Here, you are simply requiring a surcharge in exchange of accommodating tenants' (X and Y) convenience of sharing a bedroom. The reasons you outline for the surcharge (utilities, etc.) truly make sense.</p>

<p>A similar reasoning applies to the other protected classes that are listed in the aforementioned statutes.</p>

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